Hi,
How can I formulate time subscript for variables?
For example, how can I define the formula in the attached pic?
In that formula p is variable.
Thank for your attention.
Time Subscript
Time Subscript
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 Interested formula
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Re: Time Subscript
This looks like discrete time notation, and presumably the summation indicates some kind of state variable dynamics. Hard to say how to implement it without knowing what it's for.
Generically, your two choices are to implement it directly using a subscript to represent the elements of j, or to use a stock to represent the dynamics explicitly.
However, since l(t1) is independent of j in the summation, this simplifies readily:
r(t) = 1/p * p * l(t1) = l(t1)
http://metasd.com/2017/11/discretetimestinks/
Generically, your two choices are to implement it directly using a subscript to represent the elements of j, or to use a stock to represent the dynamics explicitly.
However, since l(t1) is independent of j in the summation, this simplifies readily:
r(t) = 1/p * p * l(t1) = l(t1)
http://metasd.com/2017/11/discretetimestinks/
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Re: Time Subscript
Thanks tomfid,
The correct argument is l(tj) as shown below:
I want to model a simple lending system as shown below:
In this system, loans are made every year and have a redemption period (p). Although p is constant, I want to change it in different simulation runs.
Every year we must repay 1/p of the principal of each loan until full redemption. In fact, the r(t) is the amount of repayment each year that should be calculated by p and l.
The correct argument is l(tj) as shown below:
I want to model a simple lending system as shown below:
In this system, loans are made every year and have a redemption period (p). Although p is constant, I want to change it in different simulation runs.
Every year we must repay 1/p of the principal of each loan until full redemption. In fact, the r(t) is the amount of repayment each year that should be calculated by p and l.
Time Subscript
I want to model a simple lending system as shown below:
In this system, loans are made every year and have a redemption period (p). Although p is constant, I want to change it in different simulation runs.
Every year we must repay 1/p of the principal of each loan until full redemption. In fact, the r(t) is the amount of repayment each year that should be calculated by p and l.
How can I formulate time subscript for variables?
For example, how can I define the formula in the attached pic for the loan redemption?
In this system, loans are made every year and have a redemption period (p). Although p is constant, I want to change it in different simulation runs.
Every year we must repay 1/p of the principal of each loan until full redemption. In fact, the r(t) is the amount of repayment each year that should be calculated by p and l.
How can I formulate time subscript for variables?
For example, how can I define the formula in the attached pic for the loan redemption?

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Re: Time Subscript
If I'm understanding correctly, all you need is
Code: Select all
debt redemption = loan amount / loans redemption period
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Re: Time Subscript
I've attached a model of a loan. It gets a little messy if you're interested in exact representation of compounding and payment periods, as you can see. This could be quite a bit simpler if you assumed continuous time and payments.
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