Calculating LOG sweep from Agilent ENA Network Analyzer

I have an Agilent ENA Network Analyzer that makes measurements using a LOG sweep. The method of calculating the frequency points, does not use a standard LOG calculation, it uses a modified LOG sweep in order to improve the speed. I have attached an Excel Spreadsheet which contains Frequency data retrieved from the Analyzer in Hz. It contains 6 sheets as follows: 1. Start Freq: 0.772 MHz, Stop Freq: 100 MHz: Number of Points: 801 2. Start Freq: 0.3 MHz, Stop Freq: 125 MHz: Number of Points: 401 3. Start Freq: 0.5 MHz, Stop Freq: 3600 MHz: Number of Points: 1000 4. Start Freq: 1 MHz, Stop Freq: 500 MHz: Number of Points: 10,000 5. Start Freq: 1 MHz, Stop Freq: 2200 MHz: Number of Points: 1000 6. Start Freq: 1 MHz, Stop Freq: 15 MHz: Number of Points: 10 I would like an equation/function in Excel, or Visual Basic that would allow any frequency point to be calculated, when given a start Frequency, Stop Frequency and Number of points. eg: The Frequency data for sheet 6 is as follows: 1. 1.000 2. 2.556 3. 4.111 4. 5.667 5. 7.222 6. 8.778 7. 10.333 8. 11.889 9. 13.444 10. 15.000 if this is our function: Function Calc_LOG (StartFreq#, StopFreq#, NumPoints%, PointNum%) as double In this example, if we passed it (1,15,10,7), it would return 10.333