我有一个Jupyter笔记本，其中包含markdown单元格中的python变量，如下所示：
代码单元格：
#include <iostream> using namespace std;
void a();
void b();
int main () {
a();
}
void a() {
int a=5;
int n[a];
for(int i=0;i<a;i++)
{
cin>>n[i];
}
b(n)
}
void b(int n[]) {
for (i = 0; i < n.length; i++)
print n[i]
}
降价单元格：
x = 10
如果我在笔记本中使用shift-enter执行markdown单元格，IPython-notebook-extension Python Markdown允许我动态显示这些变量。
降价单元格：
The value of x is {{x}}.
我想以编程方式执行笔记本中的所有单元格并使用以下内容将它们保存到新笔记本中：
The value of x is 10.
这将执行代码单元格，但不执行降价单元格。他们仍然看起来像这样：
import nbformat
from nbconvert.preprocessors import ExecutePreprocessor
with open('report.ipynb') as f:
nb = nbformat.read(f, as_version=4)
ep = ExecutePreprocessor(timeout=600, kernel_name='python3')
ep.preprocess(nb, {})
with open('report_executed.ipynb', 'wt') as f:
nbformat.write(nb, f)
我认为问题在于笔记本电脑不受信任。有没有办法告诉ExecutePreprocessor信任笔记本？是否有另一种方法可以在markdown单元格中以编程方式执行包含python变量的笔记本？
答案 0 :(得分：4)
ExecutePreprocessor only looks at code cells，因此您的降价单元格完全不受影响。要进行降价处理，您需要使用Python Markdown预处理器，如您所述。
不幸的是，Python Markdown预处理器系统只在实时笔记本中执行代码，它由modifying the javascript involved with rendering cells执行。修改将执行代码片段的结果存储在单元元数据中。
PyMarkdownPreprocessor类（在pre_pymarkdown.py中）设计用于在实时笔记本设置中首先渲染的笔记本上运行的nbconvert。它处理markdown单元格，用存储在元数据中的值替换{{}}模式。
但是，在您的情况下，您没有实时笔记本元数据。我遇到了类似的问题，我通过编写自己的执行预处理器解决了这个问题，该预处理器还包含处理降价单元格的逻辑：
from nbconvert.preprocessors import ExecutePreprocessor, Preprocessor
import nbformat, nbconvert
from textwrap import dedent
class ExecuteCodeMarkdownPreprocessor(ExecutePreprocessor):
def __init__(self, **kw):
self.sections = {'default': True} # maps section ID to true or false
self.EmptyCell = nbformat.v4.nbbase.new_raw_cell("")
return super().__init__(**kw)
def preprocess_cell(self, cell, resources, cell_index):
"""
Executes a single code cell. See base.py for details.
To execute all cells see :meth:`preprocess`.
"""
if cell.cell_type not in ['code','markdown']:
return cell, resources
if cell.cell_type == 'code':
# Do code stuff
return self.preprocess_code_cell(cell, resources, cell_index)
elif cell.cell_type == 'markdown':
# Do markdown stuff
return self.preprocess_markdown_cell(cell, resources, cell_index)
else:
# Don't do anything
return cell, resources
def preprocess_code_cell(self, cell, resources, cell_index):
''' Process code cell.
'''
outputs = self.run_cell(cell)
cell.outputs = outputs
if not self.allow_errors:
for out in outputs:
if out.output_type == 'error':
pattern = u"""\
An error occurred while executing the following cell:
------------------
{cell.source}
------------------
{out.ename}: {out.evalue}
"""
msg = dedent(pattern).format(out=out, cell=cell)
raise nbconvert.preprocessors.execute.CellExecutionError(msg)
return cell, resources
def preprocess_markdown_cell(self, cell, resources, cell_index):
# Find and execute snippets of code
cell['metadata']['variables'] = {}
for m in re.finditer("{{(.*?)}}", cell.source):
# Execute code
fakecell = nbformat.v4.nbbase.new_code_cell(m.group(1))
fakecell, resources = self.preprocess_code_cell(fakecell, resources, cell_index)
# Output found in cell.outputs
# Put output in cell['metadata']['variables']
for output in fakecell.outputs:
html = self.convert_output_to_html(output)
if html is not None:
cell['metadata']['variables'][fakecell.source] = html
break
return cell, resources
def convert_output_to_html(self, output):
'''Convert IOpub output to HTML
See https://github.com/ipython-contrib/IPython-notebook-extensions/blob/master/nbextensions/usability/python-markdown/main.js
'''
if output['output_type'] == 'error':
text = '**' + output.ename + '**: ' + output.evalue;
return text
elif output.output_type == 'execute_result' or output.output_type == 'display_data':
data = output.data
if 'text/latex' in data:
html = data['text/latex']
return html
elif 'image/svg+xml' in data:
# Not supported
#var svg = ul['image/svg+xml'];
#/* embed SVG in an <img> tag, still get eaten by sanitizer... */
#svg = btoa(svg);
#html = '<img src="data:image/svg+xml;base64,' + svg + '"/>';
return None
elif 'image/jpeg' in data:
jpeg = data['image/jpeg']
html = '<img src="data:image/jpeg;base64,' + jpeg + '"/>'
return html
elif 'image/png' in data:
png = data['image/png']
html = '<img src="data:image/png;base64,' + png + '"/>'
return html
elif 'text/markdown' in data:
text = data['text/markdown']
return text
elif 'text/html' in data:
html = data['text/html']
return html
elif 'text/plain' in data:
text = data['text/plain']
# Strip <p> and </p> tags
# Strip quotes
# html.match(/<p>([\s\S]*?)<\/p>/)[1]
text = re.sub(r'<p>([\s\S]*?)<\/p>', r'\1', text)
text = re.sub(r"'([\s\S]*?)'",r'\1', text)
return text
else:
# Some tag we don't support
return None
else:
return None
然后，您可以使用与发布的代码类似的逻辑处理笔记本：
import nbformat
from nbconvert.preprocessors import ExecutePreprocessor
import ExecuteCodeMarkdownPreprocessor # from wherever you put it
import PyMarkdownPreprocessor # from pre_pymarkdown.py
with open('report.ipynb') as f:
nb = nbformat.read(f, as_version=4)
ep = ExecuteCodeMarkdownPreprocessor(timeout=600, kernel_name='python3')
ep.preprocess(nb, {})
pymk = PyMarkdownPreprocessor()
pymk.preprocess(nb, {})
with open('report_executed.ipynb', 'wt') as f:
nbformat.write(nb, f)
请注意，通过包含Python Markdown预处理，您的结果笔记本文件将不再在markdown单元格中具有{{}}语法 - markdown将具有静态内容。如果生成的笔记本的收件人更改了代码并再次执行，则不会更新降价。但是，如果要导出为其他格式（例如HTML），则确实需要将{{}}语法替换为静态内容。
答案 1 :(得分：1)
2021.06.29 更新
由于 nbconvert 更改为使用 nbclient 调用 (https://github.com/jupyter/nbconvert/commit/e7bf8350435a66cc50faf29ff12df492be5d7f57#diff-bee04d71b1dfc0202a0239b1513fd81d983edc339a9734ca4f4813276feed032)，因此再次需要更新。由于run_cell不再可用，代码和markdown单元处理都需要修改。这有效：
const saveLoginInfo = async (id, name, email, phone, address, access_token) => {
try {
console.log("Data to save - " + id + ", " + name + ", " + email + ", acess token: " + access_token);
await AsyncStorage.setItem("user_id", id+"");
await AsyncStorage.setItem("user_name", name);
await AsyncStorage.setItem("user_email", email);
await AsyncStorage.setItem("user_phone", phone);
await AsyncStorage.setItem("user_address", address);
await AsyncStorage.setItem("access_token", access_token);
} catch (e) {
// saving error
console.log("Data Not SAVED - " + e);
}
}
用法保持不变。
答案 2 :(得分：0)
更新2020-07-08
@ gordon-bean提供的答案对我来说是个救命稻草。在放弃之前的最后一轮谷歌搜索中，我找到了这个答案，所以在我继续之前，我只想说谢谢！！
但是，最初的答案jupyter / nbconvert经过4年多的更改后，所提供的代码需要更新。所以这里是：
from nbconvert.preprocessors import ExecutePreprocessor
from nbconvert.preprocessors import execute
import nbformat
import re
# Taken from:
# https://stackoverflow.com/questions/35805121/execute-a-jupyter-notebook-including-inline-markdown-with-nbconvert
class ExecuteCodeMarkdownPreprocessor(ExecutePreprocessor):
def __init__(self, **kw):
self.sections = {'default': True} # maps section ID to true or false
self.EmptyCell = nbformat.v4.nbbase.new_raw_cell("")
super().__init__(**kw)
def preprocess_cell(self, cell, resources, cell_index, store_history=True):
"""
Executes a single code cell. See base.py for details.
To execute all cells see :meth:`preprocess`.
"""
if cell.cell_type not in ['code', 'markdown']:
return cell, resources
if cell.cell_type == 'code':
# Do code stuff
return self.preprocess_code_cell(cell, resources, cell_index, store_history)
elif cell.cell_type == 'markdown':
# Do markdown stuff
return self.preprocess_markdown_cell(cell, resources, cell_index, store_history)
else:
# Don't do anything
return cell, resources
def preprocess_code_cell(self, cell, resources, cell_index, store_history):
""" Process code cell.
"""
# outputs = self.run_cell(cell)
reply, outputs = self.run_cell(cell, cell_index, store_history)
cell.outputs = outputs
cell_allows_errors = (self.allow_errors or "raises-exception"
in cell.metadata.get("tags", []))
if self.force_raise_errors or not cell_allows_errors:
for out in cell.outputs:
if out.output_type == 'error':
raise execute.CellExecutionError.from_cell_and_msg(cell, out)
if (reply is not None) and reply['content']['status'] == 'error':
raise execute.CellExecutionError.from_cell_and_msg(cell, reply['content'])
return cell, resources
def preprocess_markdown_cell(self, cell, resources, cell_index, store_history):
# Find and execute snippets of code
cell['metadata']['variables'] = {}
for m in re.finditer("{{(.*?)}}", cell.source):
# Execute code
fakecell = nbformat.v4.nbbase.new_code_cell(m.group(1))
fakecell, resources = self.preprocess_code_cell(fakecell, resources, cell_index, store_history)
# Output found in cell.outputs
# Put output in cell['metadata']['variables']
for output in fakecell.outputs:
html = self.convert_output_to_html(output)
if html is not None:
cell['metadata']['variables'][fakecell.source] = html
break
return cell, resources
def convert_output_to_html(self, output):
"""Convert IOpub output to HTML
See https://github.com/ipython-contrib/IPython-notebook-extensions/blob/master/nbextensions/usability/python-markdown/main.js
"""
if output['output_type'] == 'error':
text = '**' + output.ename + '**: ' + output.evalue
return text
elif output.output_type == 'execute_result' or output.output_type == 'display_data':
data = output.data
if 'text/latex' in data:
html = data['text/latex']
return html
elif 'image/svg+xml' in data:
# Not supported
#var svg = ul['image/svg+xml'];
#/* embed SVG in an <img> tag, still get eaten by sanitizer... */
#svg = btoa(svg);
#html = '<img src="data:image/svg+xml;base64,' + svg + '"/>';
return None
elif 'image/jpeg' in data:
jpeg = data['image/jpeg']
html = '<img src="data:image/jpeg;base64,' + jpeg + '"/>'
return html
elif 'image/png' in data:
png = data['image/png']
html = '<img src="data:image/png;base64,' + png + '"/>'
return html
elif 'text/markdown' in data:
text = data['text/markdown']
return text
elif 'text/html' in data:
html = data['text/html']
return html
elif 'text/plain' in data:
text = data['text/plain']
# Strip <p> and </p> tags
# Strip quotes
# html.match(/<p>([\s\S]*?)<\/p>/)[1]
text = re.sub(r'<p>([\s\S]*?)<\/p>', r'\1', text)
text = re.sub(r"'([\s\S]*?)'",r'\1', text)
return text
else:
# Some tag we don't support
return None
else:
return None
此代码的使用与Gordon Bean报告的完全相同。