Révision 179 pobysoPythonSage/src/sageSLZ/sageNumericalOperations.sage
| sageNumericalOperations.sage (revision 179) | ||
|---|---|---|
| 1 | 1 |
print "sageNumericalOperations: loading..." |
| 2 | 2 |
|
| 3 |
|
|
| 3 | 4 |
def sno_abs_is_power_of_two(number): |
| 4 | 5 |
""" |
| 5 | 6 |
Check if the absolute value of a number is power of 2. |
| ... | ... | |
| 9 | 10 |
return is_power_of_two(abs(number)) |
| 10 | 11 |
# End sno_abs_is_power_of_two(number): |
| 11 | 12 |
|
| 13 |
def sno_float_to_rat_pow_of_two_denom(number): |
|
| 14 |
""" |
|
| 15 |
Convert a floating-point number into a rational where the denominator |
|
| 16 |
is a power of two |
|
| 17 |
""" |
|
| 18 |
## Argument checking. |
|
| 19 |
if not number.is_real(): |
|
| 20 |
return None |
|
| 21 |
# |
|
| 22 |
(sign, mantissa, exponent) = number.sign_mantissa_exponent() |
|
| 23 |
#print sign, mantissa, exponent |
|
| 24 |
precision = number.prec() |
|
| 25 |
if exponent < 0: |
|
| 26 |
denomFactorExp = -exponent |
|
| 27 |
else: |
|
| 28 |
denomFactorExp = -exponent |
|
| 29 |
if sign == 1: |
|
| 30 |
return mantissa / 2^(denomFactorExp) |
|
| 31 |
else: |
|
| 32 |
return -mantissa / 2^(denomFactorExp) |
|
| 33 |
|
|
| 34 |
|
|
| 35 |
|
|
| 12 | 36 |
print "\t...sageNumericalOperations loaded." |
Formats disponibles : Unified diff