28 lines
1.0 KiB
Go
28 lines
1.0 KiB
Go
// Copyright 2020 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package strconv
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// FormatComplex converts the complex number c to a string of the
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// form (a+bi) where a and b are the real and imaginary parts,
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// formatted according to the format fmt and precision prec.
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//
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// The format fmt and precision prec have the same meaning as in FormatFloat.
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// It rounds the result assuming that the original was obtained from a complex
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// value of bitSize bits, which must be 64 for complex64 and 128 for complex128.
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func FormatComplex(c complex128, fmt byte, prec, bitSize int) string {
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if bitSize != 64 && bitSize != 128 {
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panic("invalid bitSize")
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}
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bitSize >>= 1 // complex64 uses float32 internally
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// Check if imaginary part has a sign. If not, add one.
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im := FormatFloat(imag(c), fmt, prec, bitSize)
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if im[0] != '+' && im[0] != '-' {
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im = "+" + im
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}
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return "(" + FormatFloat(real(c), fmt, prec, bitSize) + im + "i)"
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}
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