Trying to get a specific word and the word after/before said word in a string

I'm trying to write a bot, and I ran into a problem that I cannot decide how to tackle.

For example, I have a string:

> "Today i will buy a set of buns for 4214 usd and eat it tomorrow."

How do I see if the string has "usd" in it, and if it is an int/float? If it does, how do I get the number that is near it?

The numbers may vary in their form, but general recognizable forms should be as follows:

• 1000
• -1000
• 1000.0
• -1000.0
• 1000,0
• -1000
• 0

Any further divisions into parts shouldn't be recognized.

For the string above, the expected result would be:

"4214 usd"

The regular expression would be useful here, but I am new and not familiar with them at all.

Regex is an acceptable tool,, if you can live with occasional false positives and false negatives (missed dollar amounts or things incorrectly marked as dollars).
Try this code. Since you're matching multiple formats within a string, it's hard to get all the matches at once.

See the explanations in the comment below what does the regex do.

The result will give you an array of strings, so you can process it. For example, iterate it and then remove usd and turn them into JS numbers, so you could sum them or whatever.

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

const text = `Today i will buy a set of buns for 4214 usd and eat it tomorrow. So tomorrow the budget would be total of -505.5 USD.`;

// regex to match "number USD"
const regex = /[-+]?\d+[,\.]?\d?\susd/gmi;
/*

[-+]?     # optional hyphen or plus sign
\d+       # followed by multiple numbers
[,\.]?    # followed by comma or dot, also optional
\d{1,2}?  # followed by one or two numbers, optional
\s        # followed by space
/gmi      # global, multiline, case insensitive flags: match all occurences in input data, ignore case

*/

// execute
const result = text.match(regex);


console.log('matches: ', result);


// now you can do something, for turn strings to numbers for sum or whatever..
result.forEach(res => {

  // turn it into a number or something
  const num = res.replace(/\susd/i, '').replace(',', '.');
  console.log(Number(num));

});

<!-- end snippet -->

.split

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

let str = "Today i will buy a set of buns for 4214 usd and eat it tomorrow.";
let arr = str.split(" ");
if(arr.includes("usd")){
  arr.forEach(function(item,index){
    if(!isNaN(item)){
      console.log((item + " " + arr[index+1]));
    }
  })
}

<!-- end snippet -->

    import re

def extract_amount(text):
    pattern = r'(\d+(?:,\d+)*(?:\.\d+)?)\s*(usd)'
    match = re.search(pattern, text, re.IGNORECASE)
    
    if match:
        amount = match.group(1)
        currency = match.group(2)
        return f"{amount} {currency}"
    
    return None

text = "Today i will buy a set of buns for 4214 usd and eat it tomorrow."
result = extract_amount(text)
if result:
    print(result)
else:
    print("No amount found.")

You can use that code block