python plt.plot 索引不完整

Question

p = [] 
for i in range(len(f)):
    p.append(peakdetect(H, 0.1)) 
plt.plot(Freq[p], f)

因为整个代码比较复杂所以只附上bug所在的部分。

我想绘制一个关于 Freq 和 f 的图表。而p是下面显示的索引，

[[126, 269, 409, 542],
 [145, 288, 427, 558],
 [162, 305, 443, 572],
 [177, 320, 457],
 [191, 334, 471],
 [204, 347, 483],
 [217, 359, 494],
 [228, 370, 504],
 [238, 380, 513],
 [248, 389, 521],
 [257, 398, 528],
 [265, 406, 535],
 [273, 414, 541],
 [280, 421, 546],
 [287, 428, 551],
 [294, 434],
 [300, 440],
 [306, 445],
 [312, 451],
 [317, 455],
 [322, 460],
 [327, 464],
 [331, 468],
 [336, 472],
 [340, 476],
 [344, 479],
 [348, 482],
 [351, 486],
 [355, 488],
 [358, 491],
 [361, 494],
 [364, 496],
 [367, 498],
 [370, 500],
 [373, 502],
 [375, 504],
 [378, 506],
 [380, 507],
 [383, 509],
 [385, 510],
 [387, 511],
 [389, 512],
 [392, 513],
 [394, 514],
 [395, 515],
 [397, 515],
 [399, 516],
 [401, 516],
 [403],
 [404],
 [406],
 [408],
 [409],
 [411],
 [412],
 [413],
 [415],
 [416],
 [417],
 [419],
 [420]]

其中，

f[0] corresponds to [126, 269, 409, 542]
f[1] corresponds to [145, 288, 427, 558]
f[2] corresponds to [162, 305, 443, 572]
f[3] corresponds to [177, 320, 457]
f[4] corresponds to [191, 334, 471]

...

你看，列表 p 没有完成 4 列，所以当我运行它时，它显示错误：only integers, slices (:), ellipsis (...), numpy.newaxis (None) 和整数或布尔数组是有效的索引。

因此，我认为一种方法是使用 None 来完成该列的其余部分，但我不确定。另一种方法是对列进行切片，但使用列表字符，很难操作。

peakdetect(H, 0.1) 是一个自定义函数。不用担心。

Answer 1

使用pandas 你的问题很容易解决：

import pandas as pd
a = [[126, 269, 409, 542],
 [145, 288, 427, 558],
 [162, 305, 443, 572],
 [177, 320, 457],
 [191, 334, 471],
 [204, 347, 483],
 [217, 359, 494],
 [228, 370, 504],
 [238, 380, 513],
 [248, 389, 521],
 [257, 398, 528],
 [265, 406, 535],
 [273, 414, 541],
 [280, 421, 546],
 [287, 428, 551],
 [294, 434],
 [300, 440],
 [306, 445],
 [312, 451],
 [317, 455],
 [322, 460],
 [327, 464],
 [331, 468],
 [336, 472],
 [340, 476],
 [344, 479],
 [348, 482],
 [351, 486],
 [355, 488],
 [358, 491],
 [361, 494],
 [364, 496],
 [367, 498],
 [370, 500],
 [373, 502],
 [375, 504],
 [378, 506],
 [380, 507],
 [383, 509],
 [385, 510],
 [387, 511],
 [389, 512],
 [392, 513],
 [394, 514],
 [395, 515],
 [397, 515],
 [399, 516],
 [401, 516],
 [403],
 [404],
 [406],
 [408],
 [409],
 [411],
 [412],
 [413],
 [415],
 [416],
 [417],
 [419],
 [420]]

df = pd.DataFrame(a)
df.plot()