Matrix - updating values as 0

[Suvasini]

Hi all, I have a matrix which I've uploaded in the yxmd file. The first column includes the origin stations and the header consists of destination stations. So while going from station MMCT to VAPI- there were 165 people. When I travel from station MMCT TO MMCT, from ADH to ADH- it should be 0 and I was able to specify that for all the common origin-destination stations. There is a 0 diagonal. Due to a requirement, all the numbers below the diagonal need to be zero too. So from station VAPI to MMCT, instead of 88 it should be 0 and likewise for all the cells below the diagonal. How can I do that? Please note that the first row is the header and not row no 1. Would appreciate any help. Thanks.

Origin	Class	MMCT	ADH	BVI	VAPI	BL	ST	BH	BRC	DHD	RTM	NAD	KOTA	SWM	MTJ	NDLS
MMCT	1A		0	0	165	131	3667	443	3542	208	600	126	1582	187	687	11758
ADH	1A	0		0	49	49	201	53	158	4			17	6	25	67
BVI	1A	0			14	17	302	55	432	19	43	16	101	16	136	557
VAPI	1A	88	49	7			9	2	92		5		24	5	22	303
BL	1A	64	40	6			6	1	27		3	2	0	0	6	96
ST	1A	2710	197	107	4			1	98	28	41	5	121	6	150	983
BH	1A	294	48	31		1			6		4	11	19	5	22	95
BRC	1A	2358	111	278	29	19	23	1		7	55	25	328	46	551	2819
DHD	1A	109	1	7	2		8	1	6				14	0	18	98
RTM	1A	300	1	17	6		7	1	38				55	2	38	421
NAD	1A	81		4			10	1	20				4	6	55	154
KOTA	1A	1283	6	92	14	3	140	56	482	24	52	5	0	2	108	2874
SWM	1A	152		17	1		15	1	59				2	0	9	751
MTJ	1A	1363	41	196	11	11	197	33	767	43	52	22	127	13	0	163
NDLS	1A	13079	74	636	205	50	1036	163	2666	101	517	150	4033	786	76

[Qiu]

@Suvasini 
Hope this is what you need.

[Qiu]

@Suvasini
Let me know if this works for you and would appreciate if you could mark it as accept if it does.