日本免费高清视频-国产福利视频导航-黄色在线播放国产-天天操天天操天天操天天操|www.shdianci.com

學(xué)無(wú)先后,達(dá)者為師

網(wǎng)站首頁(yè) 編程語(yǔ)言 正文

matplotlib中plt.hist()參數(shù)解釋及應(yīng)用實(shí)例_python

作者:hengheng21 ? 更新時(shí)間: 2022-10-10 編程語(yǔ)言

一、plt.hist()參數(shù)詳解

簡(jiǎn)介:
plt.hist():直方圖,一種特殊的柱狀圖。
將統(tǒng)計(jì)值的范圍分段,即將整個(gè)值的范圍分成一系列間隔,然后計(jì)算每個(gè)間隔中有多少值。
直方圖也可以被歸一化以顯示“相對(duì)”頻率。 然后,它顯示了屬于幾個(gè)類別中的每個(gè)類別的占比,其高度總和等于1。

import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib.pyplot import MultipleLocator
from matplotlib import ticker
%matplotlib inline


plt.hist(x, bins=None, range=None, density=None, weights=None, cumulative=False, bottom=None, histtype='bar', align='mid', orientation='vertical', rwidth=None, log=False, color=None, label=None, stacked=False, normed=None, *, data=None, **kwargs)

常用參數(shù)解釋:
x: 作直方圖所要用的數(shù)據(jù),必須是一維數(shù)組;多維數(shù)組可以先進(jìn)行扁平化再作圖;必選參數(shù);
bins: 直方圖的柱數(shù),即要分的組數(shù),默認(rèn)為10;
range:元組(tuple)或None;剔除較大和較小的離群值,給出全局范圍;如果為None,則默認(rèn)為(x.min(), x.max());即x軸的范圍;
density:布爾值。如果為true,則返回的元組的第一個(gè)參數(shù)n將為頻率而非默認(rèn)的頻數(shù);
weights:與x形狀相同的權(quán)重?cái)?shù)組;將x中的每個(gè)元素乘以對(duì)應(yīng)權(quán)重值再計(jì)數(shù);如果normed或density取值為T(mén)rue,則會(huì)對(duì)權(quán)重進(jìn)行歸一化處理。這個(gè)參數(shù)可用于繪制已合并的數(shù)據(jù)的直方圖;
cumulative:布爾值;如果為T(mén)rue,則計(jì)算累計(jì)頻數(shù);如果normed或density取值為T(mén)rue,則計(jì)算累計(jì)頻率;
bottom:數(shù)組,標(biāo)量值或None;每個(gè)柱子底部相對(duì)于y=0的位置。如果是標(biāo)量值,則每個(gè)柱子相對(duì)于y=0向上/向下的偏移量相同。如果是數(shù)組,則根據(jù)數(shù)組元素取值移動(dòng)對(duì)應(yīng)的柱子;即直方圖上下便宜距離;
histtype:{‘bar’, ‘barstacked’, ‘step’, ‘stepfilled’};'bar’是傳統(tǒng)的條形直方圖;'barstacked’是堆疊的條形直方圖;'step’是未填充的條形直方圖,只有外邊框;‘stepfilled’是有填充的直方圖;當(dāng)histtype取值為’step’或’stepfilled’,rwidth設(shè)置失效,即不能指定柱子之間的間隔,默認(rèn)連接在一起;
align:{‘left’, ‘mid’, ‘right’};‘left’:柱子的中心位于bins的左邊緣;‘mid’:柱子位于bins左右邊緣之間;‘right’:柱子的中心位于bins的右邊緣;
orientation:{‘horizontal’, ‘vertical’}:如果取值為horizontal,則條形圖將以y軸為基線,水平排列;簡(jiǎn)單理解為類似bar()轉(zhuǎn)換成barh(),旋轉(zhuǎn)90°;
rwidth:標(biāo)量值或None。柱子的寬度占bins寬的比例;
log:布爾值。如果取值為T(mén)rue,則坐標(biāo)軸的刻度為對(duì)數(shù)刻度;如果log為T(mén)rue且x是一維數(shù)組,則計(jì)數(shù)為0的取值將被剔除,僅返回非空的(frequency, bins, patches);
color:具體顏色,數(shù)組(元素為顏色)或None。
label:字符串(序列)或None;有多個(gè)數(shù)據(jù)集時(shí),用label參數(shù)做標(biāo)注區(qū)分;
stacked:布爾值。如果取值為T(mén)rue,則輸出的圖為多個(gè)數(shù)據(jù)集堆疊累計(jì)的結(jié)果;如果取值為False且histtype=‘bar’或’step’,則多個(gè)數(shù)據(jù)集的柱子并排排列;
normed: 是否將得到的直方圖向量歸一化,即顯示占比,默認(rèn)為0,不歸一化;不推薦使用,建議改用density參數(shù);
edgecolor: 直方圖邊框顏色;
alpha: 透明度;

返回值(用參數(shù)接收返回值,便于設(shè)置數(shù)據(jù)標(biāo)簽):
n:直方圖向量,即每個(gè)分組下的統(tǒng)計(jì)值,是否歸一化由參數(shù)normed設(shè)定。當(dāng)normed取默認(rèn)值時(shí),n即為直方圖各組內(nèi)元素的數(shù)量(各組頻數(shù));
bins: 返回各個(gè)bin的區(qū)間范圍;
patches:返回每個(gè)bin里面包含的數(shù)據(jù),是一個(gè)list。
其他參數(shù)與plt.bar()類似。

二、plt.hist()簡(jiǎn)單應(yīng)用

import matplotlib.pyplot as plt
%matplotlib inline


# 最簡(jiǎn)單,只傳遞x,組數(shù),寬度,范圍
plt.hist(data13['carrier_no'], bins=11, rwidth=0.8, range=(1,12), align='left')
plt.show()

三、plt.bar()綜合應(yīng)用

import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib.pyplot import MultipleLocator
from matplotlib import ticker
%matplotlib inline


plt.figure(figsize=(8,5), dpi=80)
# 拿參數(shù)接收hist返回值,主要用于記錄分組返回的值,標(biāo)記數(shù)據(jù)標(biāo)簽
n, bins, patches = plt.hist(data13['carrier_no'], bins=11, rwidth=0.8, range=(1,12), align='left', label='xx直方圖')
for i in range(len(n)):
    plt.text(bins[i], n[i]*1.02, int(n[i]), fontsize=12, horizontalalignment="center") #打標(biāo)簽,在合適的位置標(biāo)注每個(gè)直方圖上面樣本數(shù)
plt.ylim(0,16000)
plt.title('直方圖')
plt.legend()
# plt.savefig('直方圖'+'.png')
plt.show()

附官方參數(shù)解釋

Parameters
----------
x : (n,) array or sequence of (n,) arrays
    Input values, this takes either a single array or a sequence of
    arrays which are not required to be of the same length.

bins : int or sequence or str, optional
    If an integer is given, ``bins + 1`` bin edges are calculated and
    returned, consistent with `numpy.histogram`.

    If `bins` is a sequence, gives bin edges, including left edge of
    first bin and right edge of last bin.  In this case, `bins` is
    returned unmodified.

    All but the last (righthand-most) bin is half-open.  In other
    words, if `bins` is::

        [1, 2, 3, 4]

    then the first bin is ``[1, 2)`` (including 1, but excluding 2) and
    the second ``[2, 3)``.  The last bin, however, is ``[3, 4]``, which
    *includes* 4.

    Unequally spaced bins are supported if *bins* is a sequence.

    With Numpy 1.11 or newer, you can alternatively provide a string
    describing a binning strategy, such as 'auto', 'sturges', 'fd',
    'doane', 'scott', 'rice' or 'sqrt', see
    `numpy.histogram`.

    The default is taken from :rc:`hist.bins`.

range : tuple or None, optional
    The lower and upper range of the bins. Lower and upper outliers
    are ignored. If not provided, *range* is ``(x.min(), x.max())``.
    Range has no effect if *bins* is a sequence.

    If *bins* is a sequence or *range* is specified, autoscaling
    is based on the specified bin range instead of the
    range of x.

    Default is ``None``

density : bool, optional
    If ``True``, the first element of the return tuple will
    be the counts normalized to form a probability density, i.e.,
    the area (or integral) under the histogram will sum to 1.
    This is achieved by dividing the count by the number of
    observations times the bin width and not dividing by the total
    number of observations. If *stacked* is also ``True``, the sum of
    the histograms is normalized to 1.

    Default is ``None`` for both *normed* and *density*. If either is
    set, then that value will be used. If neither are set, then the
    args will be treated as ``False``.

    If both *density* and *normed* are set an error is raised.

weights : (n, ) array_like or None, optional
    An array of weights, of the same shape as *x*.  Each value in *x*
    only contributes its associated weight towards the bin count
    (instead of 1).  If *normed* or *density* is ``True``,
    the weights are normalized, so that the integral of the density
    over the range remains 1.

    Default is ``None``.

    This parameter can be used to draw a histogram of data that has
    already been binned, e.g. using `np.histogram` (by treating each
    bin as a single point with a weight equal to its count) ::

        counts, bins = np.histogram(data)
        plt.hist(bins[:-1], bins, weights=counts)

    (or you may alternatively use `~.bar()`).

cumulative : bool, optional
    If ``True``, then a histogram is computed where each bin gives the
    counts in that bin plus all bins for smaller values. The last bin
    gives the total number of datapoints. If *normed* or *density*
    is also ``True`` then the histogram is normalized such that the
    last bin equals 1. If *cumulative* evaluates to less than 0
    (e.g., -1), the direction of accumulation is reversed.
    In this case, if *normed* and/or *density* is also ``True``, then
    the histogram is normalized such that the first bin equals 1.

    Default is ``False``

bottom : array_like, scalar, or None
    Location of the bottom baseline of each bin.  If a scalar,
    the base line for each bin is shifted by the same amount.
    If an array, each bin is shifted independently and the length
    of bottom must match the number of bins.  If None, defaults to 0.

    Default is ``None``

histtype : {'bar', 'barstacked', 'step',  'stepfilled'}, optional
    The type of histogram to draw.

    - 'bar' is a traditional bar-type histogram.  If multiple data
      are given the bars are arranged side by side.

    - 'barstacked' is a bar-type histogram where multiple
      data are stacked on top of each other.

    - 'step' generates a lineplot that is by default
      unfilled.

    - 'stepfilled' generates a lineplot that is by default
      filled.

    Default is 'bar'

align : {'left', 'mid', 'right'}, optional
    Controls how the histogram is plotted.

        - 'left': bars are centered on the left bin edges.

        - 'mid': bars are centered between the bin edges.

        - 'right': bars are centered on the right bin edges.

    Default is 'mid'

orientation : {'horizontal', 'vertical'}, optional
    If 'horizontal', `~matplotlib.pyplot.barh` will be used for
    bar-type histograms and the *bottom* kwarg will be the left edges.

rwidth : scalar or None, optional
    The relative width of the bars as a fraction of the bin width.  If
    ``None``, automatically compute the width.

    Ignored if *histtype* is 'step' or 'stepfilled'.

    Default is ``None``

log : bool, optional
    If ``True``, the histogram axis will be set to a log scale. If
    *log* is ``True`` and *x* is a 1D array, empty bins will be
    filtered out and only the non-empty ``(n, bins, patches)``
    will be returned.

    Default is ``False``

color : color or array_like of colors or None, optional
    Color spec or sequence of color specs, one per dataset.  Default
    (``None``) uses the standard line color sequence.

    Default is ``None``

label : str or None, optional
    String, or sequence of strings to match multiple datasets.  Bar
    charts yield multiple patches per dataset, but only the first gets
    the label, so that the legend command will work as expected.

    default is ``None``

stacked : bool, optional
    If ``True``, multiple data are stacked on top of each other If
    ``False`` multiple data are arranged side by side if histtype is
    'bar' or on top of each other if histtype is 'step'

    Default is ``False``

normed : bool, optional
    Deprecated; use the density keyword argument instead.

Returns
-------
n : array or list of arrays
    The values of the histogram bins. See *density* and *weights* for a
    description of the possible semantics.  If input *x* is an array,
    then this is an array of length *nbins*. If input is a sequence of
    arrays ``[data1, data2,..]``, then this is a list of arrays with
    the values of the histograms for each of the arrays in the same
    order.  The dtype of the array *n* (or of its element arrays) will
    always be float even if no weighting or normalization is used.

bins : array
    The edges of the bins. Length nbins + 1 (nbins left edges and right
    edge of last bin).  Always a single array even when multiple data
    sets are passed in.

patches : list or list of lists
    Silent list of individual patches used to create the histogram
    or list of such list if multiple input datasets.

Other Parameters
----------------
**kwargs : `~matplotlib.patches.Patch` properties

See also
--------
hist2d : 2D histograms

Notes
-----


.. note::
    In addition to the above described arguments, this function can take a
    **data** keyword argument. If such a **data** argument is given, the
    following arguments are replaced by **data[<arg>]**:

    * All arguments with the following names: 'weights', 'x'.

    Objects passed as **data** must support item access (``data[<arg>]``) and
    membership test (``<arg> in data``).

原文鏈接:https://blog.csdn.net/weixin_45520028/article/details/113924866

欄目分類
最近更新