Skip to content

od: Fixes float formatting in scientific notation #8352

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
cakebaker merged 1 commit into from
Jul 21, 2025
Merged

od: Fixes float formatting in scientific notation #8352

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
65 changes: 46 additions & 19 deletions src/uu/od/src/prn_float.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -37,6 +37,33 @@ pub fn format_item_flo64(f: f64) -> String {
format!(" {}", format_flo64(f))
}

fn format_flo32_exp(f: f32, width: usize) -> String {
if f.abs().log10() < 0.0 {
return format!("{f:width$e}");
}
// Leave room for the '+' sign
let formatted = format!("{f:width$e}", width = width - 1);
formatted.replace('e', "e+")
}

fn format_flo64_exp(f: f64, width: usize) -> String {
if f.abs().log10() < 0.0 {
return format!("{f:width$e}");
}
// Leave room for the '+' sign
let formatted = format!("{f:width$e}", width = width - 1);
formatted.replace('e', "e+")
}

fn format_flo64_exp_precision(f: f64, width: usize, precision: usize) -> String {
if f.abs().log10() < 0.0 {
return format!("{f:width$.precision$e}");
}
// Leave room for the '+' sign
let formatted = format!("{f:width$.precision$e}", width = width - 1);
formatted.replace('e', "e+")
}

fn format_flo16(f: f16) -> String {
format_float(f64::from(f), 9, 4)
}
Expand All @@ -49,7 +76,7 @@ fn format_flo32(f: f32) -> String {

if f.classify() == FpCategory::Subnormal {
// subnormal numbers will be normal as f64, so will print with a wrong precision
format!("{f:width$e}") // subnormal numbers
format_flo32_exp(f, width) // subnormal numbers
} else {
format_float(f64::from(f), width, precision)
}
Expand All @@ -67,7 +94,7 @@ fn format_float(f: f64, width: usize, precision: usize) -> String {
if f == 0.0 || !f.is_finite() {
return format!("{f:width$}");
}
return format!("{f:width$e}"); // subnormal numbers
return format_flo64_exp(f, width); // subnormal numbers
}

let mut l = f.abs().log10().floor() as i32;
Expand All @@ -83,7 +110,7 @@ fn format_float(f: f64, width: usize, precision: usize) -> String {
} else if l == -1 {
format!("{f:width$.precision$}")
} else {
format!("{f:width$.dec$e}", dec = precision - 1)
return format_flo64_exp_precision(f, width, precision - 1); // subnormal numbers
}
}

Expand All @@ -108,11 +135,11 @@ fn test_format_flo32() {
assert_eq!(format_flo32(9_999_999.0), " 9999999.0");
assert_eq!(format_flo32(10_000_000.0), " 10000000");
assert_eq!(format_flo32(99_999_992.0), " 99999992");
assert_eq!(format_flo32(100_000_000.0), " 1.0000000e8");
assert_eq!(format_flo32(9.999_999_4e8), " 9.9999994e8");
assert_eq!(format_flo32(1.0e9), " 1.0000000e9");
assert_eq!(format_flo32(9.999_999_0e9), " 9.9999990e9");
assert_eq!(format_flo32(1.0e10), " 1.0000000e10");
assert_eq!(format_flo32(100_000_000.0), " 1.0000000e+8");
assert_eq!(format_flo32(9.999_999_4e8), " 9.9999994e+8");
assert_eq!(format_flo32(1.0e9), " 1.0000000e+9");
assert_eq!(format_flo32(9.999_999_0e9), " 9.9999990e+9");
assert_eq!(format_flo32(1.0e10), " 1.0000000e+10");

assert_eq!(format_flo32(0.1), " 0.10000000");
assert_eq!(format_flo32(0.999_999_94), " 0.99999994");
Expand All @@ -138,11 +165,11 @@ fn test_format_flo32() {
assert_eq!(format_flo32(-9_999_999.0), " -9999999.0");
assert_eq!(format_flo32(-10_000_000.0), " -10000000");
assert_eq!(format_flo32(-99_999_992.0), " -99999992");
assert_eq!(format_flo32(-100_000_000.0), " -1.0000000e8");
assert_eq!(format_flo32(-9.999_999_4e8), " -9.9999994e8");
assert_eq!(format_flo32(-1.0e9), " -1.0000000e9");
assert_eq!(format_flo32(-9.999_999_0e9), " -9.9999990e9");
assert_eq!(format_flo32(-1.0e10), " -1.0000000e10");
assert_eq!(format_flo32(-100_000_000.0), " -1.0000000e+8");
assert_eq!(format_flo32(-9.999_999_4e8), " -9.9999994e+8");
assert_eq!(format_flo32(-1.0e9), " -1.0000000e+9");
assert_eq!(format_flo32(-9.999_999_0e9), " -9.9999990e+9");
assert_eq!(format_flo32(-1.0e10), "-1.0000000e+10");

assert_eq!(format_flo32(-0.1), " -0.10000000");
assert_eq!(format_flo32(-0.999_999_94), " -0.99999994");
Expand All @@ -151,13 +178,13 @@ fn test_format_flo32() {
assert_eq!(format_flo32(-0.001), " -1.0000000e-3");
assert_eq!(format_flo32(-0.009_999_999_8), " -9.9999998e-3");

assert_eq!(format_flo32(3.402_823_3e38), " 3.4028233e38");
assert_eq!(format_flo32(-3.402_823_3e38), " -3.4028233e38");
assert_eq!(format_flo32(3.402_823_3e38), " 3.4028233e+38");
assert_eq!(format_flo32(-3.402_823_3e38), "-3.4028233e+38");
assert_eq!(format_flo32(-1.166_310_8e-38), "-1.1663108e-38");
assert_eq!(format_flo32(-4.701_977_1e-38), "-4.7019771e-38");
assert_eq!(format_flo32(1e-45), " 1e-45");

assert_eq!(format_flo32(-3.402_823_466e+38), " -3.4028235e38");
assert_eq!(format_flo32(-3.402_823_466e+38), "-3.4028235e+38");
assert_eq!(format_flo32(f32::NAN), " NaN");
assert_eq!(format_flo32(f32::INFINITY), " inf");
assert_eq!(format_flo32(f32::NEG_INFINITY), " -inf");
Expand All @@ -180,7 +207,7 @@ fn test_format_flo64() {
);
assert_eq!(
format_flo64(100_000_000_000_000_000.0),
" 1.0000000000000000e17"
" 1.0000000000000000e+17"
);

assert_eq!(format_flo64(-0.1), " -0.10000000000000001");
Expand Down Expand Up @@ -210,13 +237,13 @@ fn test_format_flo16() {
assert_eq!(format_flo16(f16::from_f32(10.0)), " 10.00");
assert_eq!(format_flo16(f16::from_f32(100.0)), " 100.0");
assert_eq!(format_flo16(f16::from_f32(1000.0)), " 1000");
assert_eq!(format_flo16(f16::from_f32(10000.0)), " 1.000e4");
assert_eq!(format_flo16(f16::from_f32(10000.0)), " 1.000e+4");

assert_eq!(format_flo16(f16::from_f32(-0.2)), " -0.2000");
assert_eq!(format_flo16(f16::from_f32(-0.02)), "-2.000e-2");

assert_eq!(format_flo16(f16::MIN_POSITIVE_SUBNORMAL), " 5.960e-8");
assert_eq!(format_flo16(f16::MIN), " -6.550e4");
assert_eq!(format_flo16(f16::MIN), "-6.550e+4");
assert_eq!(format_flo16(f16::NAN), " NaN");
assert_eq!(format_flo16(f16::INFINITY), " inf");
assert_eq!(format_flo16(f16::NEG_INFINITY), " -inf");
Expand Down
2 changes: 1 addition & 1 deletion tests/by-util/test_od.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -234,7 +234,7 @@ fn test_f32() {
]; // 0x807f0000 -1.1663108E-38
let expected_output = unindent(
"
0000000 -1.2345679 12345678 -9.8765427e37 -0
0000000 -1.2345679 12345678 -9.8765427e+37 -0
0000020 NaN 1e-40 -1.1663108e-38
0000034
",
Expand Down
Loading