diff --git a/src/main.rs b/src/main.rs index 0221937..db1fbc5 100644 --- a/src/main.rs +++ b/src/main.rs @@ -404,13 +404,18 @@ fn fmt_scientific(f: f64, precision: usize) -> String { }; let sign = if !ret.starts_with('-') { " " } else { "" }; - format!("{}{}E{}{:0>pad$}", sign, ret, exp_sign, exp, pad = 2) + format!("{}{} E{}{:0>pad$}", sign, ret, exp_sign, exp, pad = 2) } fn fmt_engineering(f: f64, precision: usize) -> String { // Format the string so the first digit is always in the first column, and remove '.'. Requested precision + 2 to account for using 1, 2, or 3 digits for the whole portion of the string // 1,000 => 1000E3 - let all = format!(" {:.precision$E}", f, precision = precision + 2).replacen(".", "", 1); + let all = format!(" {:.precision$E}", f, precision = precision) + // Remove . since it can be moved + .replacen(".", "", 1) + // Add 00E before E here so the length is enough for slicing below + .replacen("E", "00E", 1); + println!("{}", all); // Extract mantissa and the string representation of the exponent. Unwrap should be safe as formatter will insert E // 1000E3 => (1000, E3) let (num_str, exp_str) = all.split_at(all.find('E').unwrap()); @@ -471,20 +476,27 @@ mod tests { fn test_fmt_scientific() { for (f, p, s) in vec![ // Basic - (1.0, 0, " 1E+00"), - (-1.0, 0, "-1E+00"), - (100.0, 0, " 1E+02"), - (0.1, 0, " 1E-01"), - (0.01, 0, " 1E-02"), - (-0.1, 0, "-1E-01"), + (1.0, 0, " 1 E+00"), + (-1.0, 0, "-1 E+00"), + (100.0, 0, " 1 E+02"), + (0.1, 0, " 1 E-01"), + (0.01, 0, " 1 E-02"), + (-0.1, 0, "-1 E-01"), // i - (1.0, 0, " 1E+00"), + (1.0, 0, " 1 E+00"), // Precision - (-0.123456789, 3, "-1.235E-01"), - (-0.123456789, 2, "-1.23E-01"), - (-0.123456789, 2, "-1.23E-01"), - (-1e99, 2, "-1.00E+99"), - (-1e100, 2, "-1.00E+100"), + (-0.123456789, 3, "-1.235 E-01"), + (-0.123456789, 2, "-1.23 E-01"), + (-0.123456789, 2, "-1.23 E-01"), + (-1e99, 2, "-1.00 E+99"), + (-1e100, 2, "-1.00 E+100"), + // Rounding + (0.5, 2, " 5.00 E-01"), + (0.5, 1, " 5.0 E-01"), + (0.5, 0, " 5 E-01"), + (1.5, 2, " 1.50 E+00"), + (1.5, 1, " 1.5 E+00"), + (1.5, 0, " 2 E+00"), ] { assert_eq!(fmt_scientific(f, p), s); } @@ -526,6 +538,12 @@ mod tests { (0.001, 2, " 1.00 E-03"), (0.0001, 2, " 100.00 E-06"), // Rounding + (0.5, 2, " 500.00 E-03"), + (0.5, 1, " 500.0 E-03"), + (0.5, 0, " 500. E-03"), + (1.5, 2, " 1.50 E+00"), + (1.5, 1, " 1.5 E+00"), + (1.5, 0, " 2. E+00"), ] { assert_eq!(fmt_engineering(f, c), s); }