array of hashes: finding hash with min value for key

[Patrick Cotner]

I'm trying to write a proggy to help me figure out how long it will take
to pay off a credit card based on a payment value.
The card can have multiple sections with different owed amounts and
aprs.
Since the credit card companies pay off lower interest sections prior to
higher, I need to be able to determine which section has lowest apr. For
example

<code>
sections << { :type => "Purchases", wed => 840.64, :apr => 0.2474 }
sections << { :type => "Transfers", wed => 3453.45, :apr => 0.1774 }

</code>

I've set up a loop to iterate through each section and apply a finance
charge to the owed amounts. I have a variable with my payment amount.
After applying the finance charge, i need to see if section[:apr] is the
lowest of all sections, in order to apply the payment to that section
only.
How would this be done?

-Patrick

 

[dblack]

Hi --

I'm trying to write a proggy to help me figure out how long it will take
to pay off a credit card based on a payment value.
The card can have multiple sections with different owed amounts and
aprs.
Since the credit card companies pay off lower interest sections prior to
higher, I need to be able to determine which section has lowest apr. For
example

<code>
sections << { :type => "Purchases", wed => 840.64, :apr => 0.2474 }
sections << { :type => "Transfers", wed => 3453.45, :apr => 0.1774 }

</code>

I've set up a loop to iterate through each section and apply a finance
charge to the owed amounts. I have a variable with my payment amount.
After applying the finance charge, i need to see if section[:apr] is the
lowest of all sections, in order to apply the payment to that section
only.
How would this be done?

You could say:

lower = sections.find {|s| s[:apr] < section[:apr] }

and if that's non-nil, you've found a lower one.


David

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[Stefan Rusterholz]

I'm trying to write a proggy to help me figure out how long it will take
to pay off a credit card based on a payment value.
The card can have multiple sections with different owed amounts and
aprs.
Since the credit card companies pay off lower interest sections prior to
higher, I need to be able to determine which section has lowest apr. For
example

<code>
sections << { :type => "Purchases", wed => 840.64, :apr => 0.2474 }
sections << { :type => "Transfers", wed => 3453.45, :apr => 0.1774 }

</code>

I've set up a loop to iterate through each section and apply a finance
charge to the owed amounts. I have a variable with my payment amount.
After applying the finance charge, i need to see if section[:apr] is the
lowest of all sections, in order to apply the payment to that section
only.
How would this be done?

-Patrick

ri Enumerable#min
sections.min { |a,b| a[:apr] <=> b[:apr] }

Regards
Stefan

 

[Patrick Cotner]

I'm trying to write a proggy to help me figure out how long it will take
to pay off a credit card based on a payment value.
The card can have multiple sections with different owed amounts and
aprs.
Since the credit card companies pay off lower interest sections prior to
higher, I need to be able to determine which section has lowest apr. For
example

<code>
sections << { :type => "Purchases", wed => 840.64, :apr => 0.2474 }
sections << { :type => "Transfers", wed => 3453.45, :apr => 0.1774 }

</code>

I've set up a loop to iterate through each section and apply a finance
charge to the owed amounts. I have a variable with my payment amount.
After applying the finance charge, i need to see if section[:apr] is the
lowest of all sections, in order to apply the payment to that section
only.
How would this be done?

-Patrick

ri Enumerable#min
sections.min { |a,b| a[:apr] <=> b[:apr] }

Regards
Stefan

Thanks, David, but I went with Stephan's example.
I posted the (ugly) finished code over here:
http://www.ruby-forum.com/topic/123523
Thanks, Stephan!