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Writing multiple lists to a file

I have 2 lists and an output file sent to a function I am having an issue with how to do the .write statement.
I have tried using an index, but get list error.
nameList = ['james','billy','kathy']
incomeList = [40000,50000,60000]
I need to search the lists and write the name and income to a file.
for income in incomeList:
if income > 40000:
output.write(str("%10d %12.2f \n") # (this is what I can't figure out)))

You can do it like this.
nameList = ['james','billy','kathy']
incomeList = [40000,50000,60000]
for k, v in zip(nameList, incomeList):
if v > 40000:
print(k,v )
Output :-
billy 50000
kathy 60000

Maybe this is what you want:
for i,income in enumerate(incomeList):
if income > 40000:
output.write(str(nameList[i]) )

In the case of 2 lists, I would suggest using a dict.
nameIncomeList = {'james':40000,'billy':50000,'kathy':60000}
For multiple case scenario,
f=open('f1.txt','w')
for i in range(len(nameList)):
if incomeList[i]>40000:
f.write(nameList[i]+' '+incomeList[i]+'\n')
f.close()

Is there a way in Python to find a file with the smallest number in its name?

I have a bunch of documents created by one script that are all called like this:
name_*score*
*score* is a float and I need in another script to identify the file with the smallest number in the folder. Example:
name_123.12
name_145.45
This should return string "name_123.12"

min takes a key function. You can use that to define the way min is calculated:
files = [
"name_123.12",
"name_145.45",
"name_121.45",
"name_121.457"
]
min(files, key=lambda x: float((x.split('_')[1])))
# name_121.45

You can try get the number part first, and then convert it to float and sort.
for example:
new_list = [float(name[5:]) for name in YOURLIST] # trim out the unrelated part and convert to float
result = 'name_' + str(min(new_list)) # this is your result

Just wanted to say Mark Meyer is completely right on this one, but you also mentioned that you were reading these file names from a directory. In that case, there is a bit of code you could add to Mark's answer:
import glob, os
os.chdir("/path/to/directory")
files = glob.glob("*")
print(min(files, key=lambda x: float((x.split('_')[1]))))

A way to get the lowest value by providing a directory.
import os
import re
import sys
def get_lowest(directory):
lowest = sys.maxint
for filename in os.listdir(directory):
match = re.match(r'name_\d+(?:\.\d+)', filename)
if match:
number = re.search(r'(?<=_)\d+(?:\.\d+)', match.group(0))
if number:
value = float(number.group(0))
if value < lowest:
lowest = value
return lowest
print(get_lowest('./'))
Expanded on Tim Biegeleisen's answer, thank you Tim!

Search text file and save to specific variables

I have looked at the previous questions and answers to my question but can't seem to get this to work. I am very new to python so I apologize in advance for this basic question.
I am running a Monte Carlo simulation in a separate piece of software. It creates a text file output that is quite lengthy. I want to retrieve 3 values that are under one heading. I have created the following code that isolates the part of the text file I want.
f = open("/Users/scott/Desktop/test/difinp0.txt","rt")
difout = f.readlines()
f.close()
d = range(1,5)
for i, line in enumerate(difout):
if "Chi-Square Test for Difference Testing" in line:
for l in difout[i:i+5]: print(l)
This produces the following:
Chi-Square Test for Difference Testing
Value 12.958
Degrees of Freedom 10
P-Value 0.2261
Note: there is a blank line between the heading and the next line titled "Value."
There are a different statistics with the same labels in the output but I need the ones here that are under the heading "Chi-square Test for Difference Testing.
What I am looking for is to save the values into 3 variables for use later.
chivalue (which in this case would be 12.958
chidf (which in this case would be 10)
chip (which in this case would be 0.2261
I've tried to enumerate "l" and retrieve from there but I can't seem to get it to work.
Any thoughts would be greatly appreciated. Again, apologies for such a basic question.

One option is to build a function that parses the input lines and returns the variables you want
def parser(text_lines):
v, d, p = [None]*3
for line in text_lines:
if line.strip().startswith('Value'):
v = float(line.strip().split(' ')[-1])
if line.strip().startswith('Degrees'):
d = float(line.strip().split(' ')[-1])
if line.strip().startswith('P-Value'):
p = float(line.strip().split(' ')[-1])
return v,d,p
for i, line in enumerate(difout):
if "Chi-Square Test for Difference Testing" in line:
for l in difout[i:i+5]:
print(l)
value, degree, p_val = parser(difout[i:i+5])

Pythonic and concise way to construct this list?

How can I write the following code more concisely?
scores = []
for f in glob.glob(path):
score = read_score(f, Normalize = True)
scores.append(score)
I know this can be written in one or two lines without using append, but I'm a Python newbie.

Oh, I got it while browsing a related question:
scores = [read_score(f, normalize=True) for f in glob.glob(path)]

Avoiding variables as variable or list names in Python

I'd like to read in a number of text files that have the following structure:
3 560
7 470
2 680
4 620
3 640
...
The first column specifies conditions of a behavioral experiment, the second column reaction times. What I'd like to do is to create an array/list for each condition that contains the reaction times for this condition only. I've previously used Perl for this. As there are many different conditions, I wanted to avoid writing many separate elsif statements and therefore used the condition name in the array name:
push(#{condition.${cond}}, $rt); # $cond being the condition, $rt being the reaction time
For example, creating an array like this:
#condition3 = (560, 640,...);
As I got interested in Python, I wanted to see how I would accomplish this using Python. I found a number of answers discouraging the use of variables in variable names, but have to admit that from these answers I could not derive how I would create lists as described above without reverting to separate elif's for each condition. Is there a way to do this? Any suggestions would be greatly appreciated!
Thomas

A dictionary would be a good way to do this. Try something like this:
from collections import defaultdict
conditions = defaultdict(list)
for cond, rt in data:
conditions[cond].append(rt)

The following code reads the file data.txt with the format you described and computes a dictionary with the reaction times per experiment:
experiments = {}
with open('data.txt', 'r') as f:
data = [l.strip() for l in f.readlines()]
for line in data:
index, value = line.split()
try:
experiments[int(index)].append(value)
except KeyError:
experiments[int(index)] = [value]
print experiments
# prints: {2: ['680'], 3: ['560', '640'], 4: ['620'], 7: ['470']}
You can now access the reaction times per experiment using experiments[2], experiments[3], et cetera.

This is a perfect application for a dictionary, which is similar to a Perl hash:
data = {}
with open('data.txt') as f:
for line in f:
try:
condition, value = map(int, line.strip().split())
data.setdefault(condition, []).append(value)
except Exception:
print 'Bad format for line'
Now you can access your different conditions by indexing data:
>>> data
{2: [680], 3: [560, 640], 4: [620], 7: [470]}
>>> data[3]
[560, 640]

I am not sure about your question, as to why would you think about using elif conditions.
If you store a list of integers in a dictionary, the key being values of the first column a.k.a condition value, and its corresponding value a list of reaction times.
For example:
The dict would be like:
conditions['3'] -> [560, 640, ...]