巨大数据集的热图

时间:2013-01-14 12:49:57

标签: python bioinformatics heatmap

我有一个制表符分隔文件,其中包含区域和在这些区域中找到的相应生物实体(我检查了67个,因此您说每个区域都检查了这67个实体的存在与否及其频率)。

我以表格格式提供所有这些数据。

下面给出了样本数据

Region  ATF3    BCL3    BCLAF1  BDP1    BRF1    BRF2    Brg1    CCNT2   CEBPB   CHD2    CTCF    CTCFL   E2F6    ELF1
chr1:109102470:109102970    0   0   1   0   0   0   0   1   0   0   4   1   4   1
chr1:110526886:110527386    0   0   0   0   0   0   0   1   1   0   4   1   0   1
chr1:115300671:115301171    0   0   1   0   0   0   0   0   1   1   4   1   1   1
chr1:115323308:115323808    0   0   0   0   0   0   0   1   0   0   2   1   1   0
chr1:11795641:11796141  1   0   0   0   0   0   0   1   2   0   0   0   1   0
chr1:118148103:118148603    0   0   0   0   0   0   0   1   0   0   0   0   0   1
chr1:150521397:150521897    0   0   0   0   0   0   0   2   2   0   6   2   4   0
chr1:150601609:150602109    0   0   0   0   0   0   0   0   3   2   0   0   1   0
chr1:150602098:150602598    0   0   0   0   0   0   0   0   1   1   0   0   0   0
chr1:151119140:151119640    0   0   0   0   0   0   0   1   0   0   0   0   1   0
chr1:151128604:151129104    0   0   0   0   0   0   0   0   0   0   3   0   0   0
chr1:153517729:153518229    0   0   0   0   0   0   0   0   0   0   0   0   0   0
chr1:153962738:153963238    0   0   0   0   0   0   0   1   1   0   0   0   0   1
chr1:154155682:154156182    0   0   0   0   0   0   0   1   0   0   0   0   1   1
chr1:154155725:154156225    0   0   0   0   0   0   0   1   0   0   0   0   1   1
chr1:154192154:154192654    0   0   0   0   0   0   0   0   0   0   0   0   0   0
chr1:154192824:154193324    1   0   0   0   0   0   0   1   0   1   0   0   1   1
chr1:154192943:154193443    1   0   0   0   0   0   0   1   0   2   0   0   1   1
chr1:154193273:154193773    1   0   0   0   0   0   0   1   0   2   0   0   2   1
chr1:154193313:154193813    0   0   0   0   0   0   0   1   0   2   0   0   2   1
chr1:155904188:155904688    0   0   0   0   0   0   0   1   0   0   0   0   1   1
chr1:155947966:155948466    0   0   0   0   0   0   0   1   0   0   3   0   0   1
chr1:155948336:155948836    0   0   0   0   0   0   0   1   0   0   5   1   0   1
chr1:156023516:156024016    0   0   0   0   0   0   0   1   0   1   4   1   1   1
chr1:156024016:156024516    0   1   1   0   0   0   0   0   0   2   0   0   1   1
chr1:156163229:156163729    0   0   0   0   0   0   0   0   0   0   2   0   0   1
chr1:160990902:160991402    0   0   0   0   0   0   0   0   0   1   0   0   1   2
chr1:160991133:160991633    0   0   0   0   0   0   0   0   0   1   0   0   1   2
chr1:161474704:161475204    0   0   0   0   0   0   0   0   0   0   0   0   0   0
chr1:161509530:161510030    0   0   1   1   1   0   0   0   1   0   1   0   0   1
chr1:161590964:161591464    0   0   0   1   1   0   0   0   0   0   0   0   0   0
chr1:169075446:169075946    0   0   0   0   0   0   0   2   0   0   4   0   3   0
chr1:17053279:17053779  0   0   0   1   0   0   0   0   0   1   0   0   0   0
chr1:1709909:1710409    0   0   0   0   0   0   0   2   0   1   0   0   3   1
chr1:1710297:1710797    0   0   0   0   0   0   0   0   0   1   6   0   1   1

现在我怎样才能把它放在从浅色红色到暗红色的热图中(取决于频率和缺席情况下的白色)?

还有其他更好的方法来表示这类数据吗?

2 个答案:

答案 0 :(得分:4)

使用Matplotlib

import pylab as plt
import numpy as np

data = np.loadtxt("14318737.txt", skiprows=1, converters={0:lambda x: 0})
plot_data = np.ma.masked_equal(data[:,1:], 0)

plt.imshow(plot_data, cmap=plt.cm.get_cmap("Reds"), interpolation="nearest")
plt.colorbar()

plt.show()

我忽略了第一行和第一列(如果标签需要它们,我们需要更改它)。对于剩余数据,所有零值都被屏蔽(因此它们在图中显示为白色),然后将这些数据绘制为颜色编码图。

imshow有许多其他参数来控制结果,例如原点(下/上),宽高(自动/等于/ some_ratio)。

你写的地区 - 你的意思是地理区域?然后,您可能需要查看Basemap Toolkit for Matplotlib以创建颜色编码的地图。

修改

新要求,新示例

import pylab as plt
import numpy as np

fn = "14318737.txt"
with open(fn, "r") as f:
    labels = f.readline().rstrip("\n").split()[1:]
data = np.loadtxt(fn, skiprows=1, converters={0:lambda x: 0})
plot_data = np.ma.masked_equal(data[:,1:], 0)

plt.subplots_adjust(left=0.1, bottom=0.15, right=0.99, top=0.95)
plt.imshow(plot_data, cmap=plt.cm.get_cmap("Reds"), interpolation="nearest", aspect = "auto")
plt.xticks(range(len(labels)), labels, rotation=90, va="top", ha="center")
plt.colorbar()

plt.show()

现在我首先阅读第一行的标签。我将关键字参数aspect添加到imshow - 调用。我为每个因素创建标签。

此外,我使用subplots_adjust调整绘图的位置。您可以使用这些参数,直到它们满足您的需求。

现在的结果是: resulting heatmap

如果您想要y轴的其他刻度线,请使用plt.yticks,就像我的示例中的xticks一样。

答案 1 :(得分:1)

由于对我的其他答案的评论OP有关于搜索2d集群的另一个问题。这是一些答案。

从我的库eegpy获取,我使用方法find_clusters。它执行遍历2d阵列,找到高于/低于给定阈值的所有聚类。

这是我的代码:

import pylab as plt
import numpy as np
from Queue import Queue


def find_clusters(ar,thres,cmp_type="greater"):
    """For a given 2d-array (test statistic), find all clusters which
are above/below a certain threshold.
"""
    if not cmp_type in ["lower","greater","abs_greater"]:
        raise ValueError("cmp_type must be in [\"lower\",\"greater\",\"abs_greater\"]")
    clusters = []
    if cmp_type=="lower":
        ar_in = (ar<thres).astype(np.bool)
    elif cmp_type=="greater":
        ar_in = (ar>thres).astype(np.bool)
    else: #cmp_type=="abs_greater":
        ar_in = (abs(ar)>thres).astype(np.bool)

    already_visited = np.zeros(ar_in.shape,np.bool)
    for i_s in range(ar_in.shape[0]): #i_s wie i_sample
        for i_f in range(ar_in.shape[1]):
            if not already_visited[i_s,i_f]:
                if ar_in[i_s,i_f]:
                    #print "Anzahl cluster:", len(clusters)
                    mask = np.zeros(ar_in.shape,np.bool)
                    check_queue = Queue()
                    check_queue.put((i_s,i_f))
                    while not check_queue.empty():
                        pos_x,pos_y = check_queue.get()
                        if not already_visited[pos_x,pos_y]:
                            #print pos_x,pos_y
                            already_visited[pos_x,pos_y] = True
                            if ar_in[pos_x,pos_y]:
                                mask[pos_x,pos_y] = True
                                for coords in [(pos_x-1,pos_y),(pos_x+1,pos_y),(pos_x,pos_y-1),(pos_x,pos_y+1)]: #Direct Neighbors
                                    if 0<=coords[0]<ar_in.shape[0] and 0<=coords[1]<ar_in.shape[1]:
                                        check_queue.put(coords)
                    clusters.append(mask)
    return clusters

fn = "14318737.txt"
with open(fn, "r") as f:
    labels = f.readline().rstrip("\n").split()[1:]
data = np.loadtxt(fn, skiprows=1, converters={0:lambda x: 0})

clusters = find_clusters(data, 0, "greater")

plot_data = np.ma.masked_equal(data[:,1:], 0)

plt.subplots_adjust(left=0.1, bottom=0.15, right=0.99, top=0.95)
plt.imshow(plot_data, cmap=plt.cm.get_cmap("Reds"), interpolation="nearest", aspect = "auto", 
           vmin=0, extent=[0.5,plot_data.shape[1]+0.5, plot_data.shape[0] - 0.5, -0.5])
plt.colorbar()

for cl in clusters:
    plt.contour(cl.astype(np.int),[0.5], colors="k", lw=2)
plt.xticks(np.arange(1, len(labels)+2), labels, rotation=90, va="top", ha="center")


plt.show()

给出了一个形式的图像:

Plot with contour around clusters

clusters是布尔2d数组的列表(True / False)。每个arrray代表一个集群,其中每个布尔值指示特定“点”是否是此集群的一部分。您可以在任何进一步的分析中使用它。

<强> 修改

现在在群集上有更多乐趣

import pylab as plt
import numpy as np
from Queue import Queue


def find_clusters(ar,thres,cmp_type="greater"):
    """For a given 2d-array (test statistic), find all clusters which
are above/below a certain threshold.
"""
    if not cmp_type in ["lower","greater","abs_greater"]:
        raise ValueError("cmp_type must be in [\"lower\",\"greater\",\"abs_greater\"]")
    clusters = []
    if cmp_type=="lower":
        ar_in = (ar<thres).astype(np.bool)
    elif cmp_type=="greater":
        ar_in = (ar>thres).astype(np.bool)
    else: #cmp_type=="abs_greater":
        ar_in = (abs(ar)>thres).astype(np.bool)

    already_visited = np.zeros(ar_in.shape,np.bool)
    for i_s in range(ar_in.shape[0]): #i_s wie i_sample
        for i_f in range(ar_in.shape[1]):
            if not already_visited[i_s,i_f]:
                if ar_in[i_s,i_f]:
                    #print "Anzahl cluster:", len(clusters)
                    mask = np.zeros(ar_in.shape,np.bool)
                    check_queue = Queue()
                    check_queue.put((i_s,i_f))
                    while not check_queue.empty():
                        pos_x,pos_y = check_queue.get()
                        if not already_visited[pos_x,pos_y]:
                            #print pos_x,pos_y
                            already_visited[pos_x,pos_y] = True
                            if ar_in[pos_x,pos_y]:
                                mask[pos_x,pos_y] = True
                                for coords in [(pos_x-1,pos_y),(pos_x+1,pos_y),(pos_x,pos_y-1),(pos_x,pos_y+1)]: #Direct Neighbors
                                    if 0<=coords[0]<ar_in.shape[0] and 0<=coords[1]<ar_in.shape[1]:
                                        check_queue.put(coords)
                    clusters.append(mask)
    return clusters

fn = "14318737.txt"
data = []
with open(fn, "r") as f:
    labels = f.readline().rstrip("\n").split()[1:]
    for line in f:
        data.append([int(v) for v in line.split()[1:]])
data = np.array(data) #np.loadtxt(fn, skiprows=1, usecols=range(1,15))#converters={0:lambda x: 0})

clusters = find_clusters(data, 0, "greater")
large_clusters = filter(lambda cl: cl.sum()>5, clusters) #Only take clusters with five or more items
large_clusters = sorted(large_clusters, key=lambda cl: -cl.sum())

plot_data = np.ma.masked_equal(data[:,:], 0)

plt.subplots_adjust(left=0.1, bottom=0.15, right=0.99, top=0.95)
plt.imshow(plot_data, cmap=plt.cm.get_cmap("Reds"), interpolation="nearest", aspect = "auto", 
           vmin=0, extent=[-0.5,plot_data.shape[1]-0.5, plot_data.shape[0] - 0.5, -0.5])
plt.colorbar()

for cl in large_clusters:
    plt.contour(cl.astype(np.int),[.5], colors="k", lw=2)
plt.xticks(np.arange(0, len(labels)+1), labels, rotation=90, va="top", ha="center")

print "Summary of all large clusters:\n"
print "#\tSize\tIn regions"
for i, cl in enumerate(large_clusters):
    print "%i\t%i\t" % (i, cl.sum()),
    regions_in_cluster = np.where(np.any(cl, axis=0))[0]
    min_region = labels[min(regions_in_cluster)]
    max_region = labels[max(regions_in_cluster)]
    print "%s to %s" % (min_region, max_region)

plt.xlim(-0.5,plot_data.shape[1]-0.5)

plt.show()

我会过滤包含超过五个点的所有群集。我只画这些。您也可以在每个群集中使用data的总和。然后我按照它们的大小对这些大的簇进行排序,降序。

最后,我打印所有大型集群的摘要,包括它们所有集群的名称 穿过。 Large clusters only