Fun with the Sharp EL-5500 III

Fun with the Sharp EL-5500 III

See my review for the EL-5500 III here:  http://edspi31415.blogspot.com/2017/01/retro-review-sharp-scientific-computer.html

Even though the EL-5500 III has one programming space, we can fit many programs in it.  One of the great features is that how programs take relatively little space.  Obviously you can change the line numbers, the sequence of lines are most important.

Euclid Algorithm – RUN 10

10 PAUSE “GCD: A>B”

18 INPUT “A: “; A, “B: “; B

20 C = A – INT(A/B)*B

30 IF C = 0 THEN 40

32 A = B

34 B = C

36 GOTO 20

40 PRINT “GCD = “; B

46 END

My first program on the EL-5500 III.  We can probably make the coding more efficient.  PRINT with a proceeding WAIT pauses execution until [ ENTER ] is pressed.

The command END ends the program execution and allows the space to have more than one routines.

Examples:

A: 100, B: 20.  Result:  GCD = 20

A: 63, B: 60.  Result:  GCD = 3

Binomial Expansion – RUN 50

50 PAUSE “(Ax + B)^n”

55 INPUT “A: “;A, “B: “;B, “N: “,N

60 FOR I=0 TO N

65 C = FACT(N) / (FACT(I) * FACT(N-I))

70 T = C * A^(N-I) * B^I

75 PRINT T; “*x^”; N-I

80 NEXT I

85 END

The command PAUSE shows the text for about 0.85 seconds.

This program displays each coefficient one at time.

Example:  A = 3, B = -2, N = 3.  Expand (3 – 2x)^3.

Result:  27, -54, 36, -8  (27x^3 – 54x^2 + 36x – 8)

Days Between Dates – RUN 100

100 PAUSE “Days between Dates”

112 INPUT “M1:”; M1, “D1:”; D1, “Y1:”; Y1

113 INPUT “M2:”; M2, “D2:”; D2, “Y2:”; Y2

115 M = M1: D = D1: Y = Y1

117 GOSUB 140

119 F1 = F

121 M = M2: D = D2: Y = Y2

123 GOSUB 140

125 F2 = F

127 N = F2 – F1

129 PRINT “# DAYS: “; N

131 END

140 IF M > 2 THEN 150

142 X = 0: Z = Y – 1

144 GOTO 160

150 X = INT(.4 * M + 2.3): Z = Y

160 F = 365 * Y + 31* (M – 1) + D + INT(Z/4) – X

165 RETURN

If I had it my way, every calculator that isn’t a basic 4-function calculator will have a Days Between Dates function.

Example:  November 4, 1986 to January 12, 2017

M1:  11, D1: 4, Y1: 1986 

M2: 1, D2: 12, Y2: 2017

Result:  11,027

Power of a Complex Number – RUN 200

This calculates (a + bi)^n

200 PAUSE “(A + Bi)^n”

203 INPUT “A: “;A, “B: “;B, “n: “;N

205 IF A<>0 THEN 210

207 A = A^N: GOTO 220

210 R = √(A^2 + B^2)^N

212 T = ATN(B/A)*N

214 A = R * COS T

216 B = R * SIN T

220 PRINT A; “+”; B; “i”

225 END

The command <> means not equals (≠) and ATN is the arctangent function.

Examples:

(2 + 3i)^3:  A = 2, Bi = 3.  Result: -46 + 9i

(-5 + i)^2:  A = -5, Bi = 1.  Result: 24 – 10i

Error Function Approximation – RUN 250

250 PAUSE “APPROX ERF(X)”

252 CLEAR

254 DIM A(3)

256 E = 0

260 INPUT “X > 0 : “; X

262 T = RCP(1 + .47047 * X)

270 FOR I = 1 TO 3

272 READ A(I)

274 E = E + A(I) * T^I

276 NEXT I

280 DATA .3480242, -.0958798, .7478556

290 E = 1 – E * EXP(-(X^2))

292 PRINT “ERF : “, F

294 CLEAR

296 END

Use the command CLEAR to clear all the variables.  At this point, I will use this command both at the beginning and end of calculations.  The command RCP is the reciprocal.  Finally, EXP is from e^x function, not the [EXP] key.

Example:

x = 0.53, erf ≈ 0.546455764

x = 0.88, erf ≈ 7.86708E-01 = 0.786708

Keep in mind this approximation is accurate 2.5 parts in 10^-5.

Source:  Smith, Jon M.  Scientific Analysis on the Pocket Calculator  John Wiley & Sons: New York. 1975.  ISBN 0-471-79997-1

Simpson’s Rule – RUN 300

Calculates the numeric integral ∫ f(x) dx from x = L to x = U.

You can edit the function at line 342.  In BASIC-PRO mode, call up line 342 by LIST 342.  Edit as desired.

300 PAUSE “Simpsons Rule”

302 CLEAR

304 INPUT “LOWER: “; L, “UPPER: “; U, “PARTS (even): “; N

306 RADIAN

308 X = L: GOSUB 340: T = F

310 X = U: GOSUB 340: T = T + F

314 H = (U – L)/N

320 FOR I = 1 TO N-1

322 X = L + I * H: GOSUB 340

324 R = I/2 – INT(I/2)

326 IF R = 0 THEN LET T = T + 2*F

328 IF R <> 0 THEN LET T = T + 4*F

330 NEXT I

332 T = T * H/3

334 PRINT “Integral: “, T

336 CLEAR

338 END

340 REM f(x)

342 F = [insert f(X) here]

344 RETURN

Note:  I finally learn why LET is included in BASIC.  In an IF-THEN statement, if you want to assign a value or calculation to a variable, you will need a LET command.

I use a REM (remark) command on line 340.  REM is for comments and nothing said after REM is executed.

Examples:

342 F = X^2 – 1

L = -2, U = 2, N = 14.  Result:  1.333333334 (Actual: 4/3 ≈ 1.333333333)

342 F = √(X – 1)

L = 2, U = 3, N = 14.  Result: 1.218951372 (Actual:  ≈ 1.2158951416)

Dancing Star Demo – RUN 400

400 PAUSE “Dancing Star Demo”

405 CLEAR

410 S$ = “         “  (9 spaces)

415 FOR I = 1 TO 48

420 N = RND 7 + 1

425 T$ = MID$(S$, 1, N-1) + “*” + MID$(S$, N+1, 9-(N+1))

430 WAIT 15: PRINT T$

440 NEXT I

445 BEEP 3: CLEAR: END

This is just show a dancing asterisk (*) on the screen.

WAIT 15: PRINT T$:   This causes the string T$ after a quarter of a second.  WAIT operates in 1/60 seconds.

RND n:  This is the random command.  If n = 1, the result is between 0 and 1. 

BEEP n:  This makes the EL-5500 III beep n times. 

Eddie

This blog is property of Edward Shore, 2017.

Retro Review: Halo HLC-1 Lighting Calculator

Retro Review:  Halo HLC-1 Lighting Calculator

HLC-1 Lighting Calculator

Years:  Unknown

Type:  4-Function, Lighting

Memory Registers: 1 (M)

Battery: A76

The Halo HCL-1 is a professional lighting calculator and a standard 4-function calculator. The standard 4-function calculator should be self-explanatory, let’s focus on the lighting part.

The HCL-1 is abundant on eBay, and make sure you get it with the foldout manual because (1) the manual is well written and (2) it explains the process in which pre-programmed calculations are completed.  I will show a short summary of some of the pre-calculations available below.

Trig table from the manual, something we don't see in calculator manuals

Did I mention that the manual contains a short table of sines and cosines?

US units are used (length is measured in feet).

Calculating Room Cavity Ratio:

Input:

Room Width in feet, [ RW ]

Rood Length in feet, [ RL ]

Room Cavity Height in feet, [ H ]

Output:

[ RCR ] calculates the Room Cavity Ratio

The HCL-1 assumes a rectangular room.  The formula:

RCR = (5 * H * (RW + RL)) / (RW * RL)

(Source:  https://algonline.org/index.php?gloss&glossaryid=232&glossarytitle=Room+Cavity+Ratio+(RCR , Advanced Lighting Guidelines web site)

Footcandle Calculation

Input:

Coefficient of Utilization, between 0 and 1, [ CU ]

Number of lamp lumens, [ LL ]

Required footcandles, [ FC ]

Output:

Press [ CAL ].  If successful, a 0 appears in the display.

[ RCL ] [ NUM ]:  number of adjusted luminaries (lights)

[ RCL ] [ FC ]:  number of adjusted footcandles

[ RCL ] [ A ]:  area that is illuminated

[ RCL ] [ SPG ]:  fixture spacing in feet

I am thinking that this solves where to put ceiling lights on the ceiling in a grid, like in a school classroom or business office.

You can factor in the lamp lumen depreciation factor ( [ LLD ] ) AND luminaire dirt deprecation factor ( [ LDD ] ).

Final Verdict

I am glad to have the HLC 1 in my collection.  It is one of the most unique calculators ever made and was met with amusement when I posted a picture of it on my Instagram account.  Don’t lose the manual. 

Eddie

This blog is property of Edward Shore, 2017

Retro Review: Radio Shack EC-4036

Retro Review:  Radio Shack EC-4036

Radio Shack EC-4036

Radio Shack EC-4036

Company:  Radio Shack

Years:  most likely late 1980s to early 1990s

Type:  Scientific, Programming

Number of Steps: 40

Operating System: AOS (post-script)

Memory Registers: 3 (M, A, B)

Chipset:  Sharp LI3301A

Sharing the Same Chipset

According to a YouTube video from badogember csatornája, the EC-4036’s chip set is Sharp LI3301A which is shared with many other calculators such as the Citizen SRP-145, Citizen SRP-40, and Aurora TB607.  This means that this calculator line up and functions are cloned and marketed by many companies.  (Link to that video: https://www.youtube.com/watch?v=iGX4Mk3gwmM ).  The Logtech LC-604 is also part of this chip subset. 

I am thankfully that the EC-4036 is cloned (or is a clone) because I couldn’t find a manual for Radio Shack online (not even their website has a manual for this particular calculator).  Since the Citizen SRP-145N has the same chipset, its manual will have to do.  (Link:  http://calculator.citizen-europe.com/old-manuals )

There is also a discussion on the Museum of HP Calculators about the Citizen SRP-145 here:  http://www.hpmuseum.org/forum/archive/index.php?thread-6200.html 

A member of the Minimalist Club

The EC-4036 has 40 programming steps.  Furthermore, only simple programming is allowed, as there are no loops, alphabetic characters, or tests.  Unfortunately, the programming is “blind” with no way to step backwards and forwards.  Programming the EC-4036 will require either trust or writing the program down first (I always do the latter).

The good news is that you can be Statistics mode when entering programs and take advantage of the one-variable statistics functions (mean, standard and population deviation, sums Σx and

Σx^2).

There are two functions dedicated to the programming mode:

HALT:    Pauses the calculator and shows the result. This is very handy.  To continue execution, press [COMP].

[ x ]:  I originally though that this is a integer part function.  It is not, this is the Input function.  When an [ x ] is encountered, the calculator asks for a numeric input.  Press [COMP] to continue.

The EC-4036’s program is erased each time you start a new program, but with 40 steps, I image that all the programs for the EC-4036 will be short and will be easy to input when required.

When programming, program like you are actually making a calculation.  This really comes into play when you want insert a prompt step ([x]).  After pressing [x], enter a valid number to continue the calculation.  Planning is definitely a key.

Keyboard

The keys are rubbery and soft to the touch.  Thankfully, the keys are still responsive.

I wish the labeling on some to the keys could be clearer. Here are the mapping of the most confusing looking keys:

[A >A] (CD CAD):

Primary Function:  Recall A.  If a number is entered first, it multiplies it by A. 

Second Function:  Store the number in the display to register A.

Primary Function Stat Mode: Clears the last data point entered

Second Function Stat Mode: Clears all data points

[B >B] (n Σx)

Primary Function:  Recall B.  If a number is entered first, it multiplies it by B. 

Second Function:  Store the number in the display to register B.

Primary Function Stat Mode: Recall n (number of data points)

Second Function Stat Mode: Recall Σx (sum of all data points)

[ MS ] (x-bar Σx^2)  

Primary Function:  Stores the number in register M 

Second Function:  N/A

Primary Function Stat Mode: Recall the arithmetic mean of all data points

Second Function Stat Mode: Recall Σx^2 (sum of all squared data points)

[ MR ] (s σ)

Primary Function:  Recalls the number in register M 

Second Function:  N/A

Primary Function Stat Mode: Recall sample deviation (sx)

Second Function Stat Mode: Recall population deviation (σx)

[ M+ ] (DATA)

Primary Function:  Adds the number in the display to register M 

Second Function:  N/A

Primary Function Stat Mode: Enters the number as a data point

Second Function Stat Mode: N/A

Your Basic Scientific Calculator

The EC-4036 has the basic scientific functions: trigonometric, logarithmic, exponential, hyperbolic, power, factorial, and decimal/degrees-minutes-seconds conversion.

When the [2ndF] and HYP is evoked, the 2F and HYP indicators take the display.  For some reason I like this. 

Final Verdict

A nice collector calculator to have.  I wouldn’t pay a large amount of money for it however, I paid about $6.  If you like a small programming calculator or a challenge, this is one to consider.

Now for a few sample programs.

EC 4036 Program:  Percent Change

Input: 

[COMP] new [COMP] old [COMP]

Δ% = ( [1] – [2] ) / [2] * 100

Program:

[ x ]  (enter a valid number)

-

[ x ]  (enter a valid number)

MS

=

÷

MR

*

100

=

HALT

Example:  new = 52, old = 50.  Result:  Δ% = 4

EC 4036 Program: Convert from Rectangular to Polar Coordinates

This converts rectangular coordinates (A, B) to polar coordinates (limited).

r = √(A^2 + B^2), θ = atan(B/A), -90° ≤ θ ≤ 90°

Program:

[ x ]  (enter a valid number)

[ 2^nd ] [ A >A ]  (store in register A)

x^2

+

[ x ] (enter a valid number)

[ 2^nd ] [ B >B ] (store in register B)

x^2

=

√

HALT  (display r)

1

[B >B]  (recall B*1)

÷

1

[A >A] (recall A*1)

=

tan^(-1)

HALT   (display θ)

Example:  A = 3.5, B = 3.0. 

Results:  r = 4.609772229, θ = 40.60129465°, 0.708626272 radians

EC 4036:  Circumference and Area of a Circle

This program stores radius in register A and calculates the circumference and area of a circle.  Here I demonstrate the multiplication feature of [A >A].

Circumference = 2*π*r, Area = π*r^2

Input:  radius [COMP] display circumference [COMP] display area

Program:

[ x ]  (enter a valid number)

[ 2^nd ] [ A >A ] (store in register A)

*

2

*

π

=

HALT (display circumference)

π

[A >A]  (multiply π by register A)

[A >A]  (multiply A*π by register A)

=

HALT (display area)

Example:  r = 5.45. 

Results:  Circumference = 34.24335992, Area = 93.31315579

This blog is property of Edward Shore, 2017

Retro Review: Sharp Compet CS-2302 Review

Retro Review:  Sharp Compet CS-2302 Review

I’m going for a little departure from the usual types of calculators I cover.

Sharp Compet CS-2302

Company:  Sharp

Type:  Adding Machine, Paperless

Years Made: 1970s

Batteries:  AC Plug

I purchased the Compet CS-2302 from a local thrift store in Glendora, CA back in the summer of 2016. 

Adding machine, but where’s the tape?

The CS-2302 is a paperless desktop calculator, but retains the characteristics of an adding machine.  That is to add numbers, enter your number and press [ + = ].  The total is immediately displayed.  Same with subtraction, press [ - = ] to subtract. 

What is unusual about the CS-2302 is a lack of a subtotal or total key (normally marked [ ⋄ S ] and [ * T ], respectively).  Totals are cleared by pressing the clear button twice.

There is an exchange key [ ↕ ] on the CS-2302, something I don’t ever recall seeing on an adding machine.

The CS-2302 has two memories, M and I.  There are separate memory add and recall keys dedicated to both memories.

The keyboard is very solid.  The keys are responsive and it was well maintained. 

The Very Bright Display

The CS-2302 in a dark room

I think the CS-2302 wins the award for having the brightest display when it comes to calculators. 

The Red Negative Indicator

Even more amazing is the multi-color display.  Yes, in 2017 we live in a world where multi-color displays on calculators are close to common place:  HP Prime, TI-84 Plus CE, TI-nSpire CX, Casio Prizm, and Casio Classpad fx-CP400.  However, the CS-2302 is from the 1907s: a red negative sign indicator. 

Modes

The usual adding machine modes are present:  Constant Mode toggle (K), fix decimal selector complete with Add Mode, and automatic summation (Σ) toggle.

If you are not familiar with Add Mode, it is a mode where the all sums are rounded to 2 decimal places.  You are allowed to add and subtract numbers in dollars and cents without having to press the decimal point key [ . ].  Add Mode is a favorite of many office workers.

Item Counts, AVG, MU

The Item Count adds the number of addition and subtraction operations.  Pressing [IC] gives the item count and twice to clear it.

You can also use the item count to get the average of numbers added by one step with the average key ([AVG]).  Calculating the average clears the item count automatically.

Sharp called the [MU] the multiple use key in the 1970s.  Now the key is called the mark-up key.  It is true that [MU] serves multiple purposes.  Looking at the manual from similar desktop calculators from Sharp, the [MU] allows for cost, sell, markup, margin, and percent change calculations. For example:

Percent Change:  new [ + ] old [ - ] [ MU ]

Selling Price:  cost [ ÷ ] margin [ MU ]

Markup:  sell [ + ] cost [ - ] [ MU ]

Final Verdict

I love the display of the CS-2302 and the big size and steady keyboard.  I wish the CS-2302 had a totals key [ * T ] to complete calculations.  This desktop calculator, and others like it, would be a good ecological alternative for those who don’t want paper tape. 

Eddie

This blog is property of Edward Shore, 2017

Retro Review: Sharp Scientific Computer EL-5500 III

Retro Review:  Sharp Scientific Computer EL-5500 III

Company:  Sharp

Type:  Scientific, BASIC

Years Made: 1985 - 1991

Batteries:  2 CR-2032 batteries

Memory/RAM: 6,878 bytes

Basic Features

The EL-5500 III operates in two main modes:  CALC (calculator) and BASIC (programming mode).  The CALC mode has two additional sub-modes:  Matrices and Statistics (Linear Regression).   You can also convert numbers between Decimal (base 10) and Hexadecimal (base 16). 

The matrix mode uses RAM and has two matrices in storage: X and Y.  Thankfully, Sharp printed matrix operations on their hard case, includes arithmetic, scalar arithmetic, inverse, squaring, transpose, and determinant.  Given how the EL-5500 III has was released over 30 years ago, I image someone has come up with a good program to find eigenvalues.   X not only serves an input matrix but an output. With the one line screen, elements are shown one at a time.

In CALC mode, calculations are in AOS mode (algebraic, with the one-variable argument functions such as the logarithmic and trig functions are executed after the number is entered), and the equals key ( [ = ] ) completes operations.  However, in BASIC mode, calculations are entered the way they are written, and they are completed when the [ ENTER ] key is pressed.

For example:  to calculate log(6):

CALC Mode:  6 [ log ]

BASIC Mode:  [ log ] 6 [ ENTER ]

There is no built-in complex number mode.

The Keyboard

The keys are small, but no so small that I don’t have to use a stylus or aid to press them.  The keys are easy to the touch.  I am also impressed on how light the keyboard is, which is impressive for 1980s portable keyboard. Yet the keyboard is steady and the keys give a solid response.  Sharp did a great job with this model.

Programming

As mentioned before, the EL-5500 III has 6,878 bytes, somewhat comparable to the TI-74.  Also similar to the TI-74, there is only one program space.  You can fit multiple programs in the EL-5500 III as long as you organize your line numbers correctly.  However, the EL-5500 III has definable keys with the following available labels: A, S, D, F, G, H, J, K,L, ‘, Z, X, C, C, V, B, N, M, SPC. 

To label a program, follow this format:

Line number  “key” : command

…

END

Use the [DEF] key to run labeled programs. 

The EL-5500 III has a beep sound (via BEEP command).  I think am I going to start using beeps in programs when I can. 

The ability to type lower case is present through the [SML] which toggles lower case on and off.

The classic mathematical BASIC commands are available:  DELETE, NEW, GOTO, STR$, VAL, DATA, READ, DIM, FOR loops, IF tests, GOSUB, INPUT, PRINT, ON GOTO/GOSUB, and the almost completely unnecessary LET.

LIST is used instead of FETCH.

FOR loops:

FOR var = starting value TO ending value [ STEP increment ] … NEXT var

IF tests:

IF conditional test THEN do this one command if test is true

IF conditional test THEN go to this line number (no GOTO is necessary)

LET assigns a value to a variable.  However it is not required.  For example, both statements listed will store 5 to the variable A:

LET A = 5

A = 5

Strings are concentrated with a plus sign while multiple commands can be stringed together with a colon.

Line numbers are needed to organize the statements.  I wish line numbers were brought back in modern calculators that used basic.   According to the EL-5500 III manual, the available line numbers range from 1 to 65279.

Most commands also have short cut keywords.  For example, RAD., RADI., and RADIANS set radians mode, while P. and PR. can both be used for PRINT.  When entered, the EL-5500 III will complete the abbreviations with their full word counterparts.  This was created to save time.

Accessories

The EL-5500 III can be attached to a CE-126P, a combination thermal printer and cassette player interface.  Yes, the CE-126P can be connected to a compatible cassette tape player, which the player is used to record programs.     

Final Verdict

The EL-5500 III is a pleasure to hold and use.  Despite the screen being small, the text on the screen is crisp and easy to read.  The most likely place to find EL-5500 III computers for sale is eBay, which is where I purchased mine.  Prices do vary, I paid $38.  I didn’t get any accessories though.  I recommend buying one if you are interested.  

Programs using the EL-5500 III to come in the future (along with my beloved HP 71B).

P.S. The EL-5500 III is not the calculator/computer used in the 1984 movie Ghostbusters.  That was the Radio Shack TRS-80 PC-4.  (http://www.gbfans.com/equipment/other/radio-shack-pc-4-calculator/ )

Eddie

This blog is property of Edward Shore, 2017

App Review: Calculated Industries Construction App

App Review:  Calculated Industries Construction App

Company:  Calculated Industries

Platforms:  iOS, Android, Amazon

Price:  $24.99

Type:  Construction, Geometry

All pictures are taken from the app on my Amazon Kindle Fire.

Construction Master Pro Mode (4065)

Construction Master Pro Trig Mode (4080)

Two for Price of One

The Construction Pro app is really two calculators in one:

* Calculated Industries Construction Master Pro Model 4065

* Calculated Industries Construction Master Pro Trigonometric 4080

Separately, the tangible calculator would cost at retail, $69.95 and $79.95, respectively.  On the app, you can switch calculator modes by through the Preferences menu, or by pressing [Conv],  [Store] (Prefs).  A check box turns Trig mode on or off.

What are the differences between the two calculators?  Primary the third row of keys.

Pro (4065)
[Conv]		Blocks	Footing	Drywall	x^2
Primary Key	m	Length	Width	Height	%
Trig (4080)
[Conv]		Inverse (arcsine)	Inverse (arccosine)	Inverse (arctangent)	x^2
Primary key	m	Sine	Cosine	Tangent	%

On the Trig calculator, all angles are assumed to be in degrees. 

Other Tidbits

* I really like the extended Preferences menu on the app.  Some of the choices include setting the fraction resolution (from 1/2 to 1/64), set unit preferences for area and volume, choose calculation settings for Arched Wall and Irregular Jack Rafters, and set default settings for headroom height, desired stair rise height, and floor thickness.  The preferences are presented as a scrollable list on the app.

* If you like arithmetic using yards, feet, and inches, this app will do this, including rounding all result to the nearest fraction of inch (that you set in preferences).  If find this feature very convenient and fundamental.

* The app does work with degrees and degrees/minutes/seconds (DMS).  Pressing the period key [ . ] will allow you to enter DMS in this format:  degrees [ . ] minutes [ . ] seconds.  A DMS indictor will appear when numbers are in this format.  You can convert between decimal and DMS by pressing [Conv] [ . ] (dms<>deg).  This feature is available in both modes. 

* The calculator has four memory registers: register M (which M+ and M- are available, press [Rcl] [M+] to recall M), and independent registers 1, 2, and 3.

‘*  The reciprocal ( [Conv] [ ÷ ] (1/x)) and pi ( [Conv] [ + ] (π)) are available.  The change sign is a shifted command (appropriately [Conv] [ - ] (+/-)).

* One of the coolest things about the app is that if you press and hold down a key, the app will take you to the page of its user manual.  The user manuals of Construction Industries are impressive, well written, and detailed.  At least the Amazon version has this, but I’m pretty sure it is also available on the iOS and Android versions as well.  Even if you don’t have a Calculated Industries calculator or app and especially if you are considering buying one (or several), I recommend that you visit their website at http://www.calculated.com/.

Calculations included are:

* Roofs (pitches and slopes)

* Stairs

* Circles (area and circumference)

* Regular Polygons (full angle, half angle, perimeter, radius)

* Cones (area and volume)

* Spring Angles

* Cost Analysis

* Jack Rafters

As you can see, the app has a lot of calculations tailored for geometry, which is really nice.  You can solve various what-if scenarios. 

Final Verdict

If you want a construction calculator and either the following apply:

* You are budget minded

* You don’t mind or desire to a calculator app on your phone or tablet, and you are not a stickler for using hardware

I recommend buying this app, you are getting two Calculated Industries calculators for the price of one and buying the app instead of buying both calculators will save you at least $100 (spending $24.99 versus $149.90 retail).

Also, this app is very good.

I hope you enjoyed my review and until next time,

Eddie

This blog is property of Edward Shore, 2017.