To check if number is prime you have to validate is it devisible by any number in range [2, sqrt(n)]. Following code does exactly the same: import math def is_prime(n): for i in range(2, int(math.sqrt(n))+1): if n % i == 0: return False return True This method is good for small number, but if n … Read more
Check the shape of the two input arrays to plot in plt.plot(tscale1, np.array(np.hstack((0., np.abs(uamp), 0.))), …) solved python plot error of incompatible dimensions with numpy array [closed]
Opening the file without a mode defaults to opening it in readonly mode. If you want to write to it while reading, you’ve to specify the mode as r+. with open(r’G:\Programs\abc.txt’, mode=”r+”) as khand: … w+ will also open the file in r/w mode, however, it wipes the contents clean. You also use the a+ … Read more
Open your file, iterate over its lines with a for loop, split each line by commas and print second field. This should work: filepath = raw_input(‘Input file path:\n’) with open(filepath) as f: for line in f: print line.split(‘,’)[1] 2 solved Python: getting info from file? [closed]
data = conn.execute(“SELECT cost from test where name like ‘fish'”).fetchall() Also, chances are, you don’t need to use a cursor for whatever you are doing. solved Python and SQlite [closed]
A while loop that checks whether the value of account is zero would be a way to quit: while account != 0: Floating point zero is not always precisely zero: >>> 27.33 – 25.0 – 2.33 -1.7763568394002505e-15 If account is a float variable, you have to make allowances for this: while abs(account) < 0.000000001: 2 … Read more
# 2dMatrix: Your matrix # x: x-coordinate of the element for which you’re searching for neighbors # y: y-coordinate of the element for which you’re searching for neighbors def nearest_elements_2dMatrix(2dMatrix, x,y): upleft = 2dMatrix[x-1][y-1] if (x-1 >= 0 and y-1>=0) else None downleft = 2dMatrix[x-1][y+1] if (x-1 >= 0 and y+1 < len(2dMatrix)) else None … Read more
D[case] = (Dref[case]*((50/ t)^ m )) * ( math.exp((20/6)*((1/295) – (1/Temp))) It seems to be extra parentheses Try D[case] = (Dref[case]*((50/ t)^ m )) * math.exp((20/6)*((1/295) – (1/Temp))) 1 solved Python math.exp function Syntax
You are missing parenthesis around the print statements. The correct syntax is: print(“Temperature: “, temperature,” C humidity: “, humidity) Python 3 requires print statements containing text to be inside of (” “), variables inserted like: print(” text “, variable, “more text”) solved Python script: Syntax error
Set a tabulator or spaces in front of this line (depends on what you used in the above lines), so it looks like: def process_or_store(tweet): print(json.dumps(tweet)) Remind, that python does not use {} to determine where a function starts and ends. A function must be in one indentation level instead. You also forgot to close … Read more
Your existing function has at least two major problems: It doesn’t return the value from the recursive calls, meaning that it usually ends up returning None if it finishes; it uses the wrong bounds to slice the list, meaning half the time it ends up with infinite recursion. If you fix those, then all you … Read more
This is what the first parameter of the connect function is for: import sqlite3 db = sqlite3.connect(“C:/temp/MyLittleDatabase”) db.execute(“CREATE TABLE IF NOT EXISTS T(x)”) db.execute(“INSERT INTO T VALUES (42)”) cursor = db.execute(“SELECT x FROM T”) for row in cursor: print row[0] 4 solved Python: sqlite3 [closed]
in your count() function, the variable probability is created when the function called, it is not the same variable probability you declared at beginning. I think you may want to use the variable as global variable. 2 solved please correct the following code [closed]
This is algorithmic approach (w/o any lib) and it’s faster too. Performance testing with 20-30 items list, it only took less than 1 second (earlier post will take 18-19 seconds!) It’s about 50-70 times faster. It still has room to be improved, but for a reasonable size of list (40ish), it’s performant well enough (<1.5 … Read more
Try storing your data in a standard structured format such as JSON. A library for parsing JSON is included with Python. Create a file called questions.json containing: { “What are your plans for today?”: { “answers”: [“nothing”, “something”, “do not know”], “correct_answer”: 2 }, “how are you?”: { “answers”: [“well”, “badly”, “do not know”], “correct_answer”: … Read more