Month: January 2015

International Domain Names

I was helping to set up a domain for a friend the other day and I wondered whether they would like a domain in Cyrillics. Led to the question was that even possible.

I try to be aware and present but things pass me by sometimes. Particularly because I don’t really watch television. I have already posted about Cyrillics not being supported in some visual basic editors well turns out Cyrillics were not supported for URLs until 6th of May 2010.

It would be interesting to see the take up of Cyrillic URLs I note that the Cyrillic domain of Yandex url яндекс.рф re-directs to a latin version

One interesting url is the Russian President
президент.рф

Some quick research has revealed that DNS convention is old (no real surprise there) and only supports the 26 Latin characters A through Z numbers and the dash. When a non-latin based URL is placed in the address line the alphabet is re-encoded to a system called Punycode which is a way of representing a domain name with a non-DNS character set within the DNS character set. These domains are called International Domain Names (IDNs) If you wish to display IDNs properly within the address bar you need to go to Chrome settings and select the appropriate language relating to the character set of the IDN the url should appear correct otherwise you get a strange punycode translation that might be mistaken some weird non-base ten numerate system.

Doubtless Yandex did not consider this attractive as many peoples first reaction to that kind of URL would be to think that they had been re-directed to a dodgy website.

SQL Saturday coming to Edinburgh again 13 June 2015

SQL Saturday is coming to Edinburgh again Saturday 13 June 2015 I hope to attend. I have attended the two previous events I highly recommend it. Thanks must go to Jennifer Stirrup and others for taking time out to organise and speak at it.
Venue is Pollock Halls on the edge of Holyrood Park in the beautiful city of Edinburgh.

Edinburgh SQL Saturday event page

Methodology Compound Interest Calculation (Updated October 2023)

A formula that can be used for calculating compound interest

A = P( 1 + (r/n) )^nt ; R = r * 100

Where:
A= Total Accrued Amount (Principal + Interest)
P = Principal Amount
R = Rate of Interest per year as a decimal 
; r = R/100 so 4% is 4 and r would be 0.04
t = number of periods
n = compounding period
(^ indicates to the power of)

Note: Remember BODMAS when calculating with variables

Reasoning – this breaks interest down into individual compounding periods. For example, within a year when dealing with months, r would be divided by 12 if the source of interest is annual based. The individual periods are then compounded using the power over all the periods eg 24 periods for 2 years – see the examples below. NOTE the r/n is an empirical adjustment required because quoted interest rates from most sources are over a year (annual). Whenever obtaining interest rates from a source we must be careful with the r/n calculation as it may need to be ignored. If for some reason the period over which interest is defined in the source list is anything other than annually this r/n calculation may require alteration..

UK Base Interest Rates source
Bank of England Base Rate

XLS File of Base Rate changes since 1664 to June 2022
Note – I took a snap shot at June 2022 for latest go to Bank of England base rate where there is(at October 2022) a constantly updated xls file.

So for example if we want to calculate interest on £100,000 over a period of 4 years and 8 months based on an interest rate of 4.0% over the base of 0.5% over differing compound periods;
Compounded annually;
A = 100,000 ( 1 + (0.045/1) )^4.67 = £122,821.10
A = £122,821.10

Compounded Monthly;
A = 100,000 ( 1 + (0.045/12) )^56 = £123,319.40
A = £123,319.40

Compounded Daily
A = 100,000 ( 1 + (0.045/365) )^1704 = 123,376.30
A = £123,376.30
Please note : simplification this calculation leap years re-calculate if important
(^ indicates to the power of)

Methodology – How to calculate the Interest rate to be used

At the Bank of England the Monetary Policy Committee (MPC) made up of appointed members set the bank of England Base rate. When they do this it normally makes the national news. For example on the 3rd of August 2023 the Monetary Policy committee set the interest rate at 5.25%. This is the interest figure I use in the above compound interest rate when I need to calculate interest to be added by the council for holding money over a given period. But because for any given period it is unlikely that interest rates will have been uniform for the entire period it is necessary to either calculate one figure for the entire period or alternatively calculate the interest on the principle for each sub period and aggregate the figure for each of the periods. Below shows a method of calculating a single average daily interest rate for any period given changes to the rates.

So for example:

Calculate the interest rate to be used for a return of developer contributions received on the 11 May 2023 and required to be returned on the 18 August 2023 in the knowledge that the interest rate on the 11 May 2023 was 4.5% but was raised by the MPC to 5% on 22 June 2023 and then raised to 5.25% on the 03 August 2023. Develop a framework that can be used to calculate an applicable interest rate that can be used in the compounding interest rate calculation.

Average interest rate over this period is calculated as 477.75/99 or 4.825757%

This figure is consistent with the reporting by the Bank of England which changes rates on individual days rather than at the end of years or months. As such we should use the Compounding on a Daily basis to calculate the compounded interest to be returned as a result of holding this money for 99 days.

Normally, for developer contributions, additional interest will be calculated over periods of years rather than mere days but the above template can be used for any given time period. Additionally and importantly it calculates the total number of days which is also required for the compound interest rate calculation.

Project Management – Things that help lead to successful outcomes

Update its interesting to compare this post with a post I made later on the same subject..

Extraction Transformation and Load some thoughts on a large IT transfer project

FinishLine

Many roles within organisations now require good project management skills especially when it comes to implementing new IT systems and applications. But are there things that can be put in place at the beginning to improve your chance of success. I would say yes and if I am involved in a project my personal guidelines are as follows;

Step 1 : Get Stuck In
The benefit of computers is that manipulated electrons are essentially free and immortal. Try to rearrange a few. If you aren’t getting anywhere wipe them and then re-arrange them some more. Even if you are not successful you are successful in knowing that one particular arrangement cannot be achieved. You are creating a machine just like children do with Lego or engineers create with bricks and mortar except your bricks can immediately be removed and copied infinitely and each additional brick often costs nothing. In most organisations you will quickly come up against configuration and security problems. Configuration and security problems come out of nowhere often and can be project killers best to know about them up front.

Step 2 : Know your Technology
If you don’t know it at the beginning you better hope you know it at the end – go to step 1 if you are struggling with step 2 – That’s recursion for you.

Step 3 : Increment often , test constantly and try to keep focused
Set short deadlines and try to regularly meet with colleagues or clients to show progress – can be frustrating if colleagues or clients start going off on tangents especially in meetings so try to keep focused on the remit.

Step 4 : Know the Process
To date I haven’t been asked to design any systems that I have had particular difficulty in understanding the process. Undoubtedly I think this would be different if I was trying to create an application for geology exploration or for instance mapping or maybe translation. The mathematics behind those kind of applications are complicated. Most business processes tend to be remarkably simple and the simple act of normalizing the data is usually enough for me to get to grips on how the system will be used.

Step 5 : Build in redundancy
Properly normalize your data build in extra fields if you want even if they are not used – for example collecting information on individuals I always add a field for date of birth even if its not spec’d invariably someone comes along and says actually it would be useful to know what age our customers are.

Step 6 : Have privileges
There’s nothing that will slow down a project quicker if you have to hand over responsibility of tasks to uninterested individuals who are not part of the project team. Better to have those people in the team and make sure they are on board with the importance of following through with the project.

Good luck and happy hunting