FilesExpand file tree

 main

/

float_format_ints.py

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

25 lines (23 loc) · 1.15 KB

 main

/

float_format_ints.py

Copy path

Top

File metadata and controls

• Code
• Blame

25 lines (23 loc) · 1.15 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

# Test that integers format to exact values.

for b in [13, 123, 457, 23456]:

for r in range(1, 10):

e_fmt = "{:." + str(r) + "e}"

f_fmt = "{:." + str(r) + "f}"

g_fmt = "{:." + str(r) + "g}"

for e in range(0, 5):

f = b * (10**e)

title = str(b) + " x 10^" + str(e)

print(title, "with format", e_fmt, "gives", e_fmt.format(f))

print(title, "with format", f_fmt, "gives", f_fmt.format(f))

print(title, "with format", g_fmt, "gives", g_fmt.format(f))

# 16777215 is 2^24 - 1, the largest integer that can be completely held

# in a float32.

print("{:f}".format(16777215))

# 4294967040 = 16777215 * 128 is the largest integer that is exactly

# represented by a float32 and that will also fit within a (signed) int32.

# The upper bound of our integer-handling code is actually double this,

# but that constant might cause trouble on systems using 32 bit ints.

print("{:f}".format(2147483520))

# Very large positive integers can be a test for precision and resolution.

# This is a weird way to represent 1e38 (largest power of 10 for float32).

print("{:.6e}".format(float("9" * 30 + "e8")))