To represent one piece of data of multiple types using type hints in Python 3.10 or newer, you can use the pipe operator (|). Here’s how you’d use type hints in a function that typically returns a string containing the username but can also return None if the corresponding email ...
J_history=np.zeros((num_iters,1))foriterinrange(num_iters):# 对J求导,得到 alpha/m*(WX-Y)*x(i),(3,m)*(m,1)X(m,3)*(3,1)=(m,1)theta=theta-(alpha/m)*(X.T.dot(X.dot(theta)-y))J_history[iter]=computeCost(X,y,theta)returnJ_history,theta iterations=10000#迭代次数 alph...
Python program to apply function that returns multiple values to rows in pandas DataFrame # Importing Pandas packageimportpandasaspd# Create a dictionaryd={'Num': [ iforiinrange(10)]}# Create DataFramedf=pd.DataFrame(d)# Display DataFrameprint("Original DataFrame:\n",df,"\n")# Defini...
The .home() constructor returns a new path object representing the user’s home directory. This alternative constructor can be useful when you’re handling configuration files in your Python applications and projects.Finally, Path also provides a constructor called .cwd(). This method creates a ...
In this article, you have learned different ways to join two or multiple sets in Python by using the |, union(), update(), and + operators. Most of these returns a new set after joining elements and to join to an existing set use the update() function. Make sure that you need to...
Output:We use thechain functionto concatenate lists in Python. Thechain functiontakes multiple iterable arguments and returns an iterator that produces elements from those iterables. To convert the iterator into a list, we wrap it with thelist() constructor. ...
What is the map() function in Python? The map() function is a built-in function in Python that applies a specified function to all items in an iterable (e.g., a list, tuple, or string) and returns an iterator that produces the results. It takes two or more arguments: the function...
Returns the location of the currently active's site-packages lssitepackages Equivalent tols $(sitepackages_dir). add Adds the specified directories to the Python path for the currently-active virtualenv. usage: pew add [-h] [-d] dirs [dirs ...] ...
requests and all slots, even those that you don't configure for multiple values. These changes are fully backwards-compatible. Your existing code that accesses values for single-value slots continues to work unchanged. However, you must update your code to access a slot that returns multiple-...
fillna(value, method, limit, axis, inplace, downcast) The fillna() method returns the same input DataFrame or Series with the missing values filled. Advertisement - This is a modal window. No compatible source was found for this media. Example 1 We use fillna() to fill missing values ...