v/vlib/strconv/f32_f64_to_string_test.v

173 lines
3.0 KiB
V
Raw Blame History

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

/**********************************************************************
*
* Float to string Test
*
**********************************************************************/
import strconv
import math
union Ufloat32 {
mut:
f f32 = f32(0)
b u32
}
union Ufloat64 {
mut:
f f64 = f64(0)
b u64
}
fn f64_from_bits1(b u64) f64 {
mut x := Ufloat64{}
x.b = b
//C.printf("bin: %016llx\n",x.f)
return x.f
}
fn f32_from_bits1(b u32) f32 {
mut x := Ufloat32{}
x.b = b
//C.printf("bin: %08x\n",x.f)
return x.f
}
fn test_float_to_str() {
test_cases_f32 := [
f32_from_bits1(0x0000_0000), // +0
f32_from_bits1(0x8000_0000), // -0
f32_from_bits1(0xFFC0_0001), // sNan
f32_from_bits1(0xFF80_0001), // qNan
f32_from_bits1(0x7F80_0000), // +inf
f32_from_bits1(0xFF80_0000), // -inf
1,
-1,
10,
-10,
0.3,
-0.3,
1000000,
123456.7,
123e35,
-123.45,
1e23,
f32_from_bits1(0x0080_0000), // smallest float32
math.max_f32,
383260575764816448,
]
exp_result_f32 := [
"0e+00",
"-0e+00",
"nan",
"nan",
"+inf",
"-inf",
"1.e+00",
"-1.e+00",
"1.e+01",
"-1.e+01",
"3.e-01",
"-3.e-01",
"1.e+06",
"1.234567e+05",
"1.23e+37",
"-1.2345e+02",
"1.e+23",
"1.1754944e-38", // aprox from 1.1754943508 × 1038,
"3.4028235e+38",
"3.8326058e+17",
]
test_cases_f64 := [
f64_from_bits1(0x0000_0000_0000_0000), // +0
f64_from_bits1(0x8000_0000_0000_0000), // -0
f64_from_bits1(0x7FF0_0000_0000_0001), // sNan
f64_from_bits1(0x7FF8_0000_0000_0001), // qNan
f64_from_bits1(0x7FF0_0000_0000_0000), // +inf
f64_from_bits1(0xFFF0_0000_0000_0000), // -inf
1,
-1,
10,
-10,
0.3,
-0.3,
1000000,
123456.7,
123e45,
-123.45,
1e23,
f64_from_bits1(0x0010_0000_0000_0000), // smallest float64
math.max_f32,
383260575764816448,
383260575764816448,
// C failing cases
123e300,
123e-300,
5.e-324,
-5.e-324,
]
exp_result_f64 := [
"0e+00",
"-0e+00",
"nan",
"nan",
"+inf",
"-inf",
"1.e+00",
"-1.e+00",
"1.e+01",
"-1.e+01",
"3.e-01",
"-3.e-01",
"1.e+06",
"1.234567e+05",
"1.23e+47",
"-1.2345e+02",
"1.e+23",
"2.2250738585072014e-308",
"3.4028234663852886e+38",
"3.8326057576481645e+17",
"3.8326057576481645e+17",
"1.23e+302", // this test is failed from C sprintf!!
"1.23e-298",
"5.e-324",
"-5.e-324",
]
// test f32
for c,x in test_cases_f32 {
println(x)
s := strconv.f32_to_str(x,8)
s1 := exp_result_f32[c]
//println("$s1 $s")
assert s == s1
}
// test f64
for c,x in test_cases_f64 {
s := strconv.f64_to_str(x,17)
s1 := exp_result_f64[c]
//println("$s1 $s")
assert s == s1
}
// test long format
for exp := 1 ; exp < 120 ; exp++ {
a := strconv.f64_to_str_l(("1e"+exp.str()).f64())
//println(a)
assert a.len == exp + 1
b := strconv.f64_to_str_l(("1e-"+exp.str()).f64())
//println(b)
assert b.len == exp + 2
}
// test rounding str conversion
//println( ftoa.f64_to_str(0.3456789123456, 4) )
//assert ftoa.f64_to_str(0.3456789123456, 4)=="3.4568e-01"
//assert ftoa.f32_to_str(0.345678, 3)=="3.457e-01"
}