56 lines
1.2 KiB
Python
56 lines
1.2 KiB
Python
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from math import log2, ceil, floor
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BW = 5
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BE = 3
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EO = 1
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BM = BW-BE
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BO = BM-EO # BW-BE-EO
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EXP_MAX = 2**BE-1
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R_MIN = ufp_to_r(EXP_MAX, 1, BW, BE, EO)
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def r_to_ufp(r, BW, BE, EO):
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BM = BW-BE
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BO = BM-EO # BW-BE-EO
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EXP_MAX = 2**BE-1
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R_MIN = ufp_to_r(EXP_MAX, 1, BW, BE, EO)
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if r<R_MIN: # Small values
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ee = EXP_MAX
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mm = 0
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return ee, mm
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aa = floor(BM - log2(r))
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aa = max(min(aa, EXP_MAX+BO), BO)
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ee = aa - BO
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mm = round(r*2**aa)
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return ee, mm
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def ufp_to_r(ee, mm, BW, BE, EO):
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BM = BW-BE
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BO = BM-EO # BW-BE-EO
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r = mm * 2**(-BO-ee)
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return r
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for mm in range(2**BM):
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for ee in range(2**BE):
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r_exp = ufp_to_r(ee, mm, BW, BE, EO)
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ee_exp, mm_exp = r_to_ufp(r_exp, BW, BE, EO)
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r_exp2 = ufp_to_r(ee_exp, mm_exp, BW, BE, EO)
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#print("r={} r_exp={} mm={} ee={}".format(r, r_exp, mm_exp, ee_exp))
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print("mm={} ee={} r={} ".format(mm, ee, r_exp))
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print("mm={} ee={} r={} ".format(mm_exp, ee_exp, r_exp2))
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print("---------------------------------------------------")
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r=1.5625e-2
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#r=3.1249999999999997e-2
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ee, mm = r_to_ufp(r, BW, BE, EO)
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r2 = ufp_to_r(ee, mm, BW, BE, EO)
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