diff options
Diffstat (limited to 'src/pkg/strconv/ftoa.go')
| -rw-r--r-- | src/pkg/strconv/ftoa.go | 54 |
1 files changed, 27 insertions, 27 deletions
diff --git a/src/pkg/strconv/ftoa.go b/src/pkg/strconv/ftoa.go index 55e618881..0f3f50fe7 100644 --- a/src/pkg/strconv/ftoa.go +++ b/src/pkg/strconv/ftoa.go @@ -14,12 +14,13 @@ import "math" // TODO: move elsewhere? type floatInfo struct { - mantbits uint; - expbits uint; - bias int; + mantbits uint; + expbits uint; + bias int; } -var float32info = floatInfo{ 23, 8, -127 } -var float64info = floatInfo{ 52, 11, -1023 } + +var float32info = floatInfo{23, 8, -127} +var float64info = floatInfo{52, 11, -1023} func floatsize() int { // Figure out whether float is float32 or float64. @@ -72,12 +73,12 @@ func Ftoa(f float, fmt byte, prec int) string { } func genericFtoa(bits uint64, fmt byte, prec int, flt *floatInfo) string { - neg := bits>>flt.expbits>>flt.mantbits != 0; - exp := int(bits>>flt.mantbits) & (1<<flt.expbits - 1); - mant := bits & (uint64(1)<<flt.mantbits - 1); + neg := bits >> flt.expbits >> flt.mantbits != 0; + exp := int(bits >> flt.mantbits)&(1 << flt.expbits - 1); + mant := bits&(uint64(1) << flt.mantbits - 1); switch exp { - case 1<<flt.expbits - 1: + case 1 << flt.expbits - 1: // Inf, NaN if mant != 0 { return "NaN"; @@ -93,7 +94,7 @@ func genericFtoa(bits uint64, fmt byte, prec int, flt *floatInfo) string { default: // add implicit top bit - mant |= uint64(1)<<flt.mantbits; + mant |= uint64(1) << flt.mantbits; } exp += flt.bias; @@ -106,7 +107,7 @@ func genericFtoa(bits uint64, fmt byte, prec int, flt *floatInfo) string { // The shift is exp - flt.mantbits because mant is a 1-bit integer // followed by a flt.mantbits fraction, and we are treating it as // a 1+flt.mantbits-bit integer. - d := newDecimal(mant).Shift(exp - int(flt.mantbits)); + d := newDecimal(mant).Shift(exp-int(flt.mantbits)); // Round appropriately. // Negative precision means "only as much as needed to be exact." @@ -127,7 +128,7 @@ func genericFtoa(bits uint64, fmt byte, prec int, flt *floatInfo) string { case 'e', 'E': d.Round(prec+1); case 'f': - d.Round(d.dp+prec); + d.Round(d.dp + prec); case 'g', 'G': if prec == 0 { prec = 1; @@ -151,16 +152,16 @@ func genericFtoa(bits uint64, fmt byte, prec int, flt *floatInfo) string { // if precision was the shortest possible, use precision 6 for this decision. eprec := prec; if shortest { - eprec = 6 + eprec = 6; } exp := d.dp - 1; if exp < -4 || exp >= eprec { - return fmtE(neg, d, prec - 1, fmt + 'e' - 'g'); + return fmtE(neg, d, prec-1, fmt+'e'-'g'); } return fmtF(neg, d, max(prec - d.dp, 0)); } - return "%" + string(fmt); + return "%"+string(fmt); } // Round d (= mant * 2^exp) to the shortest number of digits @@ -185,7 +186,7 @@ func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) { // d = mant << (exp - mantbits) // Next highest floating point number is mant+1 << exp-mantbits. // Our upper bound is halfway inbetween, mant*2+1 << exp-mantbits-1. - upper := newDecimal(mant*2+1).Shift(exp-int(flt.mantbits)-1); + upper := newDecimal(mant*2 + 1).Shift(exp-int(flt.mantbits)-1); // d = mant << (exp - mantbits) // Next lowest floating point number is mant-1 << exp-mantbits, @@ -196,14 +197,14 @@ func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) { minexp := flt.bias + 1; // minimum possible exponent var mantlo uint64; var explo int; - if mant > 1<<flt.mantbits || exp == minexp { - mantlo = mant - 1; + if mant > 1 << flt.mantbits || exp == minexp { + mantlo = mant-1; explo = exp; } else { - mantlo = mant*2-1; + mantlo = mant*2 - 1; explo = exp-1; } - lower := newDecimal(mantlo*2+1).Shift(explo-int(flt.mantbits)-1); + lower := newDecimal(mantlo*2 + 1).Shift(explo-int(flt.mantbits)-1); // The upper and lower bounds are possible outputs only if // the original mantissa is even, so that IEEE round-to-even @@ -252,8 +253,8 @@ func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) { // %e: -d.ddddde±dd func fmtE(neg bool, d *decimal, prec int, fmt byte) string { - buf := make([]byte, 3+max(prec, 0)+30); // "-0." + prec digits + exp - w := 0; // write index + buf := make([]byte, 3 + max(prec, 0) + 30); // "-0." + prec digits + exp + w := 0; // write index // sign if neg { @@ -322,7 +323,7 @@ func fmtE(neg bool, d *decimal, prec int, fmt byte) string { // %f: -ddddddd.ddddd func fmtF(neg bool, d *decimal, prec int) string { - buf := make([]byte, 1+max(d.dp, 1)+1+max(prec, 0)); + buf := make([]byte, 1 + max(d.dp, 1) + 1 + max(prec, 0)); w := 0; // sign @@ -352,10 +353,10 @@ func fmtF(neg bool, d *decimal, prec int) string { buf[w] = '.'; w++; for i := 0; i < prec; i++ { - if d.dp+i < 0 || d.dp+i >= d.nd { + if d.dp + i < 0 || d.dp + i >= d.nd { buf[w] = '0'; } else { - buf[w] = d.d[d.dp+i]; + buf[w] = d.d[d.dp + i]; } w++; } @@ -379,7 +380,7 @@ func fmtB(neg bool, mant uint64, exp int, flt *floatInfo) string { n++; w--; buf[w] = byte(exp%10 + '0'); - exp /= 10 + exp /= 10; } w--; buf[w] = esign; @@ -405,4 +406,3 @@ func max(a, b int) int { } return b; } - |