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Commit b7484ea7 by Piotr Mitros
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Adds testability to the EIA file

parent 70b38fc3
Showing with 101 additions and 5 deletions
common/lib/sandbox-packages/eia.py
"""
Standard resistor codes.
Standard resistor values.
Commonly used for verifying electronic components in circuit classes are
standard values, or conversely, for generating realistic component
values in parameterized problems. For details, see:
http://en.wikipedia.org/wiki/Electronic_color_code
"""
# pylint: disable=invalid-name
# r is standard name for a resistor. We would like to use it as such.
import math
import numbers
E6 = [10, 15, 22, 33, 47, 68]
E12 = [10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82]
E24 = [10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82, 11, 13, 16, 20,
24, 30, 36, 43, 51, 62, 75, 91]
E48 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 105,
127, 154, 187, 226, 274, 332, 402, 487, 590, 715, 866, 110, 133,
162, 196, 237, 287, 348, 422, 511, 619, 750, 909, 115, 140, 169,
205, 249, 301, 365, 442, 536, 649, 787, 953]
E96 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 102,
124, 150, 182, 221, 267, 324, 392, 475, 576, 698, 845, 105, 127,
154, 187, 226, 274, 332, 402, 487, 590, 715, 866, 107, 130, 158,
191, 232, 280, 340, 412, 499, 604, 732, 887, 110, 133, 162, 196,
237, 287, 348, 422, 511, 619, 750, 909, 113, 137, 165, 200, 243,
294, 357, 432, 523, 634, 768, 931, 115, 140, 169, 205, 249, 301,
365, 442, 536, 649, 787, 953, 118, 143, 174, 210, 255, 309, 374,
453, 549, 665, 806, 976]
E192 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 101,
123, 149, 180, 218, 264, 320, 388, 470, 569, 690, 835, 102, 124,
150, 182, 221, 267, 324, 392, 475, 576, 698, 845, 104, 126, 152,
184, 223, 271, 328, 397, 481, 583, 706, 856, 105, 127, 154, 187,
226, 274, 332, 402, 487, 590, 715, 866, 106, 129, 156, 189, 229,
277, 336, 407, 493, 597, 723, 876, 107, 130, 158, 191, 232, 280,
340, 412, 499, 604, 732, 887, 109, 132, 160, 193, 234, 284, 344,
417, 505, 612, 741, 898, 110, 133, 162, 196, 237, 287, 348, 422,
511, 619, 750, 909, 111, 135, 164, 198, 240, 291, 352, 427, 517,
626, 759, 920, 113, 137, 165, 200, 243, 294, 357, 432, 523, 634,
768, 931, 114, 138, 167, 203, 246, 298, 361, 437, 530, 642, 777,
942, 115, 140, 169, 205, 249, 301, 365, 442, 536, 649, 787, 953,
117, 142, 172, 208, 252, 305, 370, 448, 542, 657, 796, 965, 118,
143, 174, 210, 255, 309, 374, 453, 549, 665, 806, 976, 120, 145,
176, 213, 258, 312, 379, 459, 556, 673, 816, 988]
def iseia(r, valid_types=(E6, E12, E24)):
'''
Check if a component is a valid EIA value.
By default, check 5% component values
'''
# Step 1: Discount things which are not numbers
if not isinstance(r, numbers.Number) or \
r < 0 or \
math.isnan(r) or \
math.isinf(r):
return False
# Special case: 0 is an okay resistor
if r == 0:
return True
# Step 2: Move into the range [100, 1000)
while r < 100:
r = r * 10
while r >= 1000:
r = r / 10
E24 = [10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82, 11, 13, 16, 20, 24, 30, 36, 43, 51, 62, 75, 91]
# Step 3: Discount things which are not integers, and cast to int
if abs(r - round(r)) > 0.01:
return False
r = int(round(r))
E48 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 105, 127, 154, 187, 226, 274, 332, 402, 487, 590, 715, 866, 110, 133, 162, 196, 237, 287, 348, 422, 511, 619, 750, 909, 115, 140, 169, 205, 249, 301, 365, 442, 536, 649, 787, 953]
# Step 4: Check if we're a valid EIA value
for type_list in valid_types:
if r in type_list:
return True
if int(r / 10.) in type_list and (r % 10) == 0:
return True
E96 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 102, 124, 150, 182, 221, 267, 324, 392, 475, 576, 698, 845, 105, 127, 154, 187, 226, 274, 332, 402, 487, 590, 715, 866, 107, 130, 158, 191, 232, 280, 340, 412, 499, 604, 732, 887, 110, 133, 162, 196, 237, 287, 348, 422, 511, 619, 750, 909, 113, 137, 165, 200, 243, 294, 357, 432, 523, 634, 768, 931, 115, 140, 169, 205, 249, 301, 365, 442, 536, 649, 787, 953, 118, 143, 174, 210, 255, 309, 374, 453, 549, 665, 806, 976]
return False
E192 = [100, 121, 147, 178, 215, 261, 316, 383, 464, 562, 681, 825, 101, 123, 149, 180, 218, 264, 320, 388, 470, 569, 690, 835, 102, 124, 150, 182, 221, 267, 324, 392, 475, 576, 698, 845, 104, 126, 152, 184, 223, 271, 328, 397, 481, 583, 706, 856, 105, 127, 154, 187, 226, 274, 332, 402, 487, 590, 715, 866, 106, 129, 156, 189, 229, 277, 336, 407, 493, 597, 723, 876, 107, 130, 158, 191, 232, 280, 340, 412, 499, 604, 732, 887, 109, 132, 160, 193, 234, 284, 344, 417, 505, 612, 741, 898, 110, 133, 162, 196, 237, 287, 348, 422, 511, 619, 750, 909, 111, 135, 164, 198, 240, 291, 352, 427, 517, 626, 759, 920, 113, 137, 165, 200, 243, 294, 357, 432, 523, 634, 768, 931, 114, 138, 167, 203, 246, 298, 361, 437, 530, 642, 777, 942, 115, 140, 169, 205, 249, 301, 365, 442, 536, 649, 787, 953, 117, 142, 172, 208, 252, 305, 370, 448, 542, 657, 796, 965, 118, 143, 174, 210, 255, 309, 374, 453, 549, 665, 806, 976, 120, 145, 176, 213, 258, 312, 379, 459, 556, 673, 816, 988]
if __name__ == '__main__':
# Test cases. All of these should return True
print iseia(100) # 100 ohm resistor is EIA
print not iseia(101) # 101 is not
print not iseia(100.3) # Floating point close to EIA is not EIA
print iseia(100.001) # But within floating point error is
print iseia(1e5) # We handle big numbers well
print iseia(2200) # We handle middle-of-the-list well
# We can handle 1% components correctly; 2.2k is EIA24, but not EIA48.
print not iseia(2200, (E48, E96, E192))
print iseia(5490e2, (E48, E96, E192))
print iseia(2200)
print not iseia(5490e2)
print iseia(1e-5) # We handle little numbers well
print not iseia("Hello") # Junk handled okay
print not iseia(float('NaN'))
print not iseia(-1)
print not iseia(iseia)
print not iseia(float('Inf'))
print iseia(0) # Corner case. 0 is a standard resistor value.
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