Thursday, April 9, 2015

HP 50g: Bolt Pattern, Solar Irradiance, Thermal Noise, Regular Polygons, Center of Mass (Matrix of Masses)

HP 50g:   Bolt Pattern, Solar Irradiance, Thermal Noise, Regular Polygons,

Center of Mass (Matrix of Masses)



Bolt Pattern: BOLTPAT



Input:
4:  xc:   x coordinate, center
3:  yc:   y coordinate, center
2:  n:  number of bolts
1:  d:  diameter of the circle

Program:
<< DEG OVER 1 – → xc yc n d k
<< { } 0 k FOR I 360 I * n / DUP COS d 2 / * xc +
SWAP SIN d 2 / * yc + (0,1) * + + NEXT
DUPDUP 2 GET SWAP 1 GET – ABS >> >>

Output: 
2:  list of bolts (x+yi)
1:  OC-Distance

Solar Irradiance:  IRRAD


Input:
5:  es:   elevation of the sun (as decimal degrees)
4:  as:   azimuth of the sun from south going east (as decimal degrees)
3:  ep:   elevation of the panel (as decimal degrees)
2:  ap:   azimuth of the panel from south going east (as decimal degrees)
1:  ib:  the sun’s power or irradiance (usually 1,000 or 1,367 W/m^2)

Program:
<< → es as ep ap ib
<< DEG ep COS es SIN * ep SIN es COS * as ap – COS *
+ ACOS DUP COS ib * >> >>

Output:
2:  incidence angle
1:  surface radiance

Thermal Noise:  THNOISE


Input:
3:  R:  resistance (Ω)
2:  T:   temperature (K)
1:  B:   noise bandwidth (Hz)

Program:
<< → R T B
<< T R * B * 4 * 1.3806488E-23 * √
T B * LOG 10 * 198.599167802 -  >> >>

Output:
2:  Voltage (Volts)
1:  Noise Power (dB)

Regular Polygon:  Internal Angle and Area:  RPOLYG


Input:
2:  s:  side length
1:  n:  number of sides


Program: 
<< DEG DUP INV 360 * NEG 180 + UNROT 4 / SWAP SQ * SWAP DUP UNROT 2 / TAN * >>

Output:
2:  Interior Angle
1:  Area

Center of Mass using Matrix:  CENTERMTX


Input:
1:  Matrix of Masses

Program:
<< DUP SIZE OBJ→ DROP → M R C
<< M 1  C START 1 NEXT C →ARRY * AXL ∑LIST

M 1 C FOR I I NEXT C 1 2 →LIST →ARRY * TRAN
1 R START 1 NEXT R 1 2 →LIST →ARRY * OBJ→ DROP

M TRAN 1 R FOR I I NEXT R 1 2 →LIST →ARRY * TRAN
1 C START 1 NEXT C 1 2  →LIST →ARRY * OBJ→ DROP

→ tm rw cw
<< rw tm / cw tm  / {1,2} →ARRY >> >> >>

Output:
[[ x center of mass point,  y center of mass point ]]



Special Note:  April 11 will mark the fourth anniversary of this blog.  I appreciate the readers and followers of this blog and thank you for that, and the comments.  Best always,  Eddie!


This blog is property of Edward Shore.  2015.

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