BLYNK
HOME       📲 GETTING STARTED       📗 DOCS       ❓HELP CENTER       👉 SKETCH BUILDER

LOVE THE CSV EXPORT! Two Things needed, Request From Hardware and Time Range


#1

Hi Guys,

Export to csv from the History Graph works beautifully. If this could be invoked from the hardware side with a specified time range, that would make it ideal!

i.e. BLYNK_EXPORT((V1,V2,V3),UNIXTIMEBEGIN,UNIXTIMEEND)

I love the idea of pushing the data off of your server to other locations for the sake of keeping you total stored data (and therefore operating costs) minimal.

I know you probably would prefer it to get pushed through the app, because then folks need to purchase the history graph widget to accomplish this (and I totally understand that), but I am guessing you guys could figure out how to filter export requests from the hardware side that only works for the history-graphed data… or maybe it is worth it to you to just make it accessible to all data on your server for free… or perhaps a new widget, similar to ‘push notification’ or ‘email’, that would allow the export of any data collected in the project in the previous month that has been written to the blynk server. It is invoked from the hardware, but only works after installing the ‘export’ widget in the app.


Export line chart data to excel file
#2

Hello. Indeed you already could do that (however without time begin/end filters) via HTTP API. Regarding implementing this on hardware side… I don’t think we will do that because hardware usually are very slow and limited in memory so such request for data may crash it that will happen often I believe.


#3

But how can you even export csv from history from app?


#4

@monaco http://docs.blynk.cc/#widgets-displays-history-graph


#5

Hi, getting the data is extremely easy. I am struggling with converting the numeric value of the date to a readable date-time format. I am using Excel 2013. I could use some help on which function to use.

I have an export containing 1 dataset: temperature / date-time

Thank you.


#6

@tonk type “Excel date” into the search facility.


#7

Super! Works like a charm. I searched Excel…


#8

Hi could you give a guide how - I tried to change date format in Excel without luck
thx, gernot


#9

Hi folks, the time provided from the Blynk server is Unix time. Or in other words, the number provided is how many milliseconds have passed since January 1, 1970. Excel’s ‘date’ format is the number of days since January 1, 1900. Therefore to convert the Blynk provided Unix time into the Excel format, enter the following equation into a blank cell: =“UNIXTIME” (select the cell with the unix time) / 1000 (converts to seconds) / 60 (converts to minutes) / 60 (converts to hours) / 24 (converts to days) + DATE(1970,1,1) (excel function that returns the Excel Date for a given real date. This formula without the notes is as follows:

= “UNIXTIME” / 1000 / 60 / 60 / 24 + DATE(1970,1,1)

This will return a number that excel will recognize as the actual time of the reading. The formula returned 12/25/2016 2:20 PM for the first line in the table posted by “tonk” above. Tinkering on Christmas day I see! =D


Why history graph has an exponential value?
Retrieval of Blynk data
#10

Thx @evancraig22 you made my day!


#11

Sorry for the late response, I was on holiday… I basically used the same formula as described by evancraig


#12

Scrrenshot of the @evancraig22 formula in use.


#13

Could you show me step by step. I can not fix it!! Thanks!


#16

@BolCao try downloading this file and look at the formulae and formatting etc https://thechariot.co.uk/excel/time.xls

@Gunner Unixtime hasn’t changed for “years” :slight_smile:


#18

Its Great
I tried and found very useful

Thanks for valuable efforts


#19

Thanks for the file !


#20